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So always we measure interaction between those. So I think you have noticed this slide is the last part. But firstly I would like to mention, for example, value characterization. So this will be a flow chart. For example, before you start measurement, you want to understand what kind of physics we are in the world.

What kind of characteristics do you have? Your materials. So you have to have questions. What do you want to get? What do you get? What do you understand? The phenomena of your material. So you have to define. What do you want? And then the target properties. For example, the proof material interaction is that inside the core, for example, electronic structure.

Or if you want some surface, means surface binding or some dangling bone, whatever. Or something that's positive, particularly non-particle. You want to know the exact vindication of your materials. And then, also case, there are the non-particle cases kept with the organic. Then if you want interaction between your core, the broken aromaterial with surface, the what kind of surface?

or how strong I think because, right? So those kind, what do you want? What do you want? So you have to find out, you have to take time. And then this kind of phenomena, which one is most probably more active, right? So sometimes you can, you want to produce will be a strong interaction between some photon energy or

some x-ray or electron beam, those kind. So you have to select what kind of energy you have to select. But one thing, these energies have to not deformation of your eobotry. For example, if you try high energy of any flu, sometimes your samples can destroy it. or sometimes deformation.

sometimes some degradation. So you have to prove, you have to find right proof energy and then what kind of techniques do you have to select. So generally you have to select proper proof energy and then techniques. Means for example, when you select proof energy, for example proof energy means like you might expect what kind of phenomena will be

will be generated from the new experiment. But sometimes you have to put in this case, for example, diffraction phenomena, your major properties are diffraction phenomena. Like something, diffraction, means like diffraction phenomena not only with some electron beam, x-ray. So, S-ray diffraction or electron diffraction

different, you improve energy, but phenomena will be the same. So that means your X-ray diffraction pattern or electron diffraction pattern, result have to be the same. Because you measure the phenomena, so even though the different energy, but the same phenomena with your materials, your result has to be the same. But sometimes it is different. For For example, if you measure XRD and then you define something,

crystal structure. But if you measure some electron, the electron microscope and get the electron diffraction pattern, then same material but structure is different. What do you mean? This one maybe some experiment is something wrong. Or during the measurement somehow your structure can be changed. Right? Because extra energy and electron-billion energy

So, more like your samples are highly reactive with some electrical beam or somehow to actually beam, then you have to select proper energy source, right? This is why you guys say phenomena, why you do literally different levels, because you need to double check. But you don't have to, you don't have to stay, otherwise you have to work, you have to work, advanced technique,

So, and then, anyhow, you got any signal, right? Any signal you might get. But typically you have to careful about it. Because normally, very strong pigs are already known results. For example, always you want to compare with something you were experiencing the condition, somehow something changed, right?

that changes need to better device, right? So need to, something change means always, most of the case, your signal is very weak, weak signal, not strong signal. Strong signal means like already you know. So always you have to care for very weak signal or very small energy change. For example, normally if you measure something, properties, x-axis will be your parameters, condition.

And then with the interval, in many cases your energy is different, then you get y-axis intensity or something, probability. Probability is really y-axis, x-axis will be your full energy. So you have to be careful, very small shiftiness, shiftiness of your x-axis, right?

Intensity means that is maybe something interaction change, right? That is information. You want to understand information will be that result, right? So if you get any data, signal, you have to carefully take a look, not just ignore. Small change means you anyway, that is information. You are conditioned. And then you have to make, sometimes you directly compare or you have to make some model to interpret.

And then that's why you can extract material property. That difference is what change means that is interaction. What kind of interaction? Because you are your crew and then your material interaction with your experiment condition. So you have to find out what is the meaning. Not just change the shiftiness or not change the intensity. That is your interaction information has.

So you have to prove it. So once you get this piece, then you can understand the of your device performance because that phenomena related to your performance. But same time, in this case you also want to care for. Because, for example, normally when you have characterization of your materials, always you have to have

original materials. You measure. But when you make a device, for example, always you characterize the sum in solution or in period. So you define properties. And then you make a device. Device is process. So during making the device, you probably there are many different layers. Or you can offer a temperature. You can use some air.

something like this. Because that's what I'm saying. So basically this phenomena why you need to clarify because you want to make a better device or better understanding what kind of phenomena can have to improve the device. But in this case when you process your device always you put some additional energy not usually the same as This is it. So you have to

double check because many cases students misconduct because you believe you measure these properties in the old the materials have the same properties but it's different. So whatever, for example simply if you measure another particle in solution and after making a piller always peak shift it, always stuck shift, for example because if you make it in piller in general, original particles are prospecting, means like

Electron and couplings are much higher than in individual nanoparticles. That's why your particles, your absorption, PRPX will be red shifted. So for example, if you want to make some LED emitted at, for example, 520, right? So you measure in solution, usually your PRPX are emitted at 520. But

Basically you want to make the right emitting device with a pill, right? Then with 520 nanometer, pure emission nanoponics always emitted, if you make some LED device, emitted at least 540 or sometimes 50. That means your target emitting is different, right? So this one, you can understand the phenomena, but always when you make the device,

Exactly you have to compare this is right, right? The properties. For example, if you want to make some 450 anything device, then you have to compare how much is stock shift between insolution and pillow. Right? So if you want to target device at 540, then you have to calculate, depends on your material composition or particle size,

You have to define how much it starts in your case. Then, in this case, you cannot utilize 520. You have to make something utilize 510 or 570. Then these materials can show exact emitting, the right emitting, right? So those kinds, those kinds of basic understanding are very important. But whatever menu, any device, you have to

So, let's try it. Final. Final properties are one instead. So, that's right. This is entering your materials. And then, every time, when you try this materials, always you need to double check after making the final device. That's why you can't understand exactly your device performance.

Inesimanto, degradation, what is the origin? That's that understanding of your origin. That's our playground for the characterization. So, we have to make sure exactly what you want, know what kind of information, right? And then the proof, the proof, the proof energy, This is, can that sum?

some deformation or degradation or sometimes face change not affect or lose time. And then also the penetration. Penetration this means each information, for example this is a similar, for example sometimes you can get inside the core or surface or something that you let us stretch out the shell or inner shell. And then depends on the data information, your true energy have to change.

Sometimes you have to high energy or sometimes you have to know the weak energy. So you have to select. And your properties are surface related or vertical related. So it depends on this, you have to choose. And then during the measurement, first, very important calculation each instrument.

Do not ignore calibration. For example, do not believe your colleague. Sometimes, for example, when you, most of the case, as I say, most of your result will be very weak signal, not very strong signal, right? So, means like if you not properly calibrate your instrument, maybe that weak signal from the artifact. You are used to.

So even though you say that just you consider your colleague is very smart, this guy is a very good job, then he calibrate so I can utilize, for example, this one. So every time, when you do any instrument, you have to first have to check this is the right condition. So you have to calibrate. Because calibrate means when you understand baseline.

before changing any measurement, you might understand. And also, background subtract. So, telegram, background subtract, right? The background subtract is, for example, most of the case, you have some background signal, right? But your measurement is real signal, right? So, sometimes your signal is very weak, then sometimes the content, the background,

So the liquid you cannot distinguish with your actual signal to your background, means like noise. So always, most of these measurements you have to define clear signal to noise ratio. Noise means like originally the liquid have some background. Sometimes, for example, simply, I'll read the talk later, for example absorption spectrum, simple mass absorption spectrum.

If absorption means like the reference and the sample, if you can create both the same energy and then the one side, for example, this is reference with the sample, this is the middle sample, then you can compare. Without the sample, there is nothing observable. But with the sample something, the absorption will be happening, right? But in this case reference, reference means exactly you have to identify or solvents have to try it because

It's different, one side is glass, one side is quartz, one side is solvent is toriane, one side is the other particles are hexane or water. It will be that medium. Refrative indexes can be different. So, background, already, already, this background will be something different. So, you cannot see more precise results you cannot get from.

So always, calibration, background substrate means you reference your sector, condition. Always, always same. And then, detector. So, in this case, you have to move, and then you have some internet. Always, oh, you can get signal, because you might get something detector. Detector means, detector is there are several different kinds of detectors. Therefore, simply you want to some,

qualitative. You don't need to precise. It means like high resolution of detector. Or sometimes you have to utilize very precisely and detect some range. It means higher resolution detector is always more complicated. So you have to try it

the proper detector. Sometimes you have to, your signal is very noisy or sometimes very weak signal, then you have to find out integration time. For example, if you increase integration time, then more multiple signals you can detect. This is a little bit simple, but all the other is relationship here.

and then you have to minimize the signal to noise ratio. And then, in many cases, instrument itself. Instrument means it's not perfect device. So always you have to be careful. And then, the instrument itself is now properly works.

After the experiment, you have to find out visually the peak intensity, high, low, or the flagship, right? This is not, you have to find out the meaning of your signal. So, the physical, subchemical phenomena.

You have to understand, not just means no operation. So operation means like, technician maybe, whatever TM, even though I ask you to get permission for self-use, but this is something technical manner, right? You want to not operate, you want not want to operate. You want to get some science meaning, right? So, but...

So again, this is what you get. This is what I want to say. So there are different kinds of sources. Cloud, which you can try. Electron, x-ray, ion, or photon. Magnetic field or thermal. This is most probably you want. You can select energy. But this energy, fluid energy,

What kind of interaction you can expect. So the interaction between your cell phone and then on the right detector. Detector you got something. Interaction is maybe probably with your energy will be something that scattering or polarization or absorption, ionization or deflection. That kind of interaction will be happening.

But again, this kind of phenomena will be whatever you select energy will be. This is phenomena, interaction with your battler. So end up, result has to have the same. If you find a different energy log, if you get something different, then it will be, again, really important. There's something happening. Something happening.

And this similar generation was probably something like EVs, which is a CEM, TEM, or EDX spectrum. Or differential phenomena, when you define crystal structure, you utilize differential phenomena. X-ray differential or electron differential will be, or you can, I started to put down the selected area of electron differential. This result has some crystal.

information. So I have to say, spectra, or the X-Pens or Lama, or scattering phenomena, that are elastic or in-electric scattering, it will be your infiltrate electron or some of the photons, will be some scattering phenomena, in-elastic or elastic. Because your energy, input energy is preserved or something deformation, that is

Electrons, for example, your elastic scattering have your core of your atoms, information have. Or something elastic means like somehow energy change. So that energy somehow changes the energy related to your something. Your outer set or inner set or k-set or k-set or any set or any set or any set.

and those kinds of electrons are information. So you can get spectrum, spectrum phenomenon. Intensity, normally intensity is probably if you get spectrum, I will share later. Normally intensity means like sum of your signal. So for example, if you are similar because you measure something, or some other materials,

Same amplitude will be constructive interference will be amplitude. Means that your intensity is increased. Increase means that some orientation or some phenomena have dominantly appear with this interaction. Or, for example, if you are not handling it.

magnetic properties. But when you do, if you apply some magnetic field as proof energy, then you can get something, magnetic properties. Or in front of the thermal energy you can get something, which is the key thing about this. This is a lot if you change the temperature, your gravity change or some telemetry change you can make, you can understand.

Pitch temperature, this one, something, face deformation or something burning, something like that. Something, information you can get from the summer energy. So this is all we, our playground in the instrument analysis. So another thing, most of the cases you have to try to, your, You get signal, you have to

quantitatively analyze, not qualitatively. So intensity means when you can quantitatively analyze how much percent increase with your experimental condition. So something change, then how much intensity change? How much the intensity of information or something change try to understand quantitatively. Means all the signals you can define.

quantitatively because if you know the original, right? That equation means you can always compare. That's clear. Try to quantitative analysis. Quantitative. Not quantitative. So then why do you take this material analysis? And I told you most of the case, 70% of our

the electrolytes, electrolytes the photo energy. Because photo energy is quite simple. If you electrolytes the electromagnetic radiation, for example, there are so many range we can select. In this case, our solar sunlight. So always, these sunlight have all kinds of energy sources.

you can see gamma ray x-ray, violet, visible, infrared, or microwave, or radio. This is we can neutralize fluid. So simply, you can neutralize hydride, hydride, then you can select whatever, like if you want something, or x-ray, or infrared, or microwave, or radio. All these energies are

always these energies are, you need to know, relationship, this is energy, right? And this is frequency, and then this is weightless. So this is, for example, always our right energy is duality, right? So weight function and then photon, energy function, right? So always you have to easily can understand, comfort, relationship between. This is energy.

are related with frequency and then wavelengths. Sometimes we just measure different wavelengths, but different wavelengths means like this is related energy. Energy means your transition energy, right? This wavelength, if you want to understand some, for example, some atoms, I want to transition between K-sher and M-sher, right? This is really some energy, right?

So if you excite something, wave-lax, this is energy, right? So this energy is already enough to stimulate. That occupied electron, because either electrons are ejected, then electron will be again coming back, right? So that much energy will be emitted, right? Always this is the general phenomena. That is the information. So always you have to

easily can convert energy's relations, frequency and wavelength. So energy frequency will be proportional, right? But wavelength energy is inversed, proportional, right? So wavelength is shorter, smaller, then energy is higher. Wavelength is longer, then your energy will be low. So that's why But Yugoyi river, Yugoyi, means like,

below 350 nanometer. That's why energy is high because your wave energy is low, then energy is high. That means your value is high. But even though if you want to excite something about your energy, for example, if you apply those 3.0 electron volt energy, if you want to He said some kid here. What is it for?

Cotton energy is very simple because you can select more than 3.0 electron volt cotton energy easily you can inside your sample, right? But if you apply some electric period up to 303 electron volts, how much electron volts you have to apply? If you want to apply heat energy, you never get 3.0 electron volt energy. But control is very simple because

you already select very simply. So that's why most our instrument characterization is very good energy source. So representing optical techniques, there are, you can easily access instruments, for example, you will use spectroscopic.

you can measure absorption. Potoluminescence, for example, this is luminescence. Emitting, something, the emitting, material, semi-conducting materials, you can simply measure and then you can distinguish what is the banding gap, what is the state of the surface state, the third state. More detail, if you measure some time-resolved absorption, so here's spectroscopy or time-resolved absorption spectroscopy, you can get.

lifetime of your carrier. For example, even though your transition, excitation, always your electric carrier has a lifetime. Travel speed or some lifetime. So you can simply measure PM, intensity is how much, which wavelength is limiting, that's it. But if you have more detailed understanding of your carrier, your dynamic or phenomena, if you measure time-resolved PM or time-resolved

absorption spectroscopy have those kinds of more detail inside information you can get. So, Rana spectroscopy and FTIR spectroscopy, in this case you utilize FTIR range, fluid. So, in this case normally you can get something the molecular binding or even though you are something

Crescent structure or something, isotropic, something, pyramidal, those kind of results you can get. This one also utilize cotton energy. The range is near IR. So that's why FT, IR spectroscopy, fluid transform, IR spectroscopy. In this range, we utilize four IR, or light source. And ellipsometry or replantometry, if you do something,

like a simple-based device, you have to carefully understand it. For example, most cases your properties are related to reproductive index or extinction coefficient. So most cases if you do some of the film-related experiments, you have to define your medium, your circle, your source state. You all did help me understand the interactive index of your

Because that phenomena, many things are related with the refractive index. So you can measure the refractive index or the distinction coefficient or the phenotype sequence or any other. In the direction you can get allisometry and the refractometry. Or sometimes not only for some of the signals, you can get something visible.

image technique with those kind of measurement. And also next week I will tell you about optical microscope because even though last week I did it towards you, optical microscope is the simplest scope. Means like you can get some image, right? Very simple microscope, but if you go So like a quarter, most cases if you want to, if you're working on some,

nanomaterial that is small dimension of your device it's not easy to characterize with a microscope scale so most case recent some experiment is related with a microscope means this spectroscopy will combine with the microscope right so in this case your true energy will be how can you reach your center?

always utilize optical microscope, then this true energy has to travel with optical passway with your optical microscope. Depends on your optical microscope object of the lens, means like magnification, your sample resolution will be changed. Most probably, recent instrument, for example, micro-PL, microgrammer, micro-ILETS carrier,

all these instruments, these are just combining. Microscope, not macroscope. Then you have to understand the optical microscope is not simply get some magnifying, some image, because your optical microscope has to have your definitely effect your signal to the modulation. So you probably

Understanding optical microscope.

So actually we can understand the band structure or carrier dynamic or phonon dispersion or surface interface or track some optical content. Those kinds of flow, absorption or emission, scattering, reflection. So those kinds of interactions you can get.

So this is, I think everyone already know, but just demand. So, what is radiation and spectroscopy? I told you that. Peer spectroscopy, absorption spectroscopy, lamar spectroscopy, right? Radiation is in your provenance. So energy propagates from your space medium.

And then spectroscopy, definition of spectroscopy, you measure measurement and this is important. Interpretation of your probe and your material's interaction. And electromagnetic radiation. There are two functions, right? There are wave function and photon, particle, energy function, right? So,

always is the same. Wave length and energy always correlated. So sometimes, for example, wave function, like your wave function always oscillate, right? Oscillate with the different wave length, so frequency different, but with the amplitude, intensity different. But always wave model propagates what's an interference. What kind of interpidals?

Particle model you absorption or emission, this is energy talk. Both ways. Characterization, sometimes you have to understand the chrome wave function, sometimes you have to understand the energy. But both ways. Energy wave length is always correlated. What do you want? What do you have to know? Wave function, wave properties or more? Electromagnetic radiation.

Interference, destructive or constructive. Because your wave function is the same phase, constructive means like amplitude. Your phase is out of phase, means destructive. So means your energy, if you excite your photo energy, will be this right, have a wave, right? And then this wave, this energy will stimulate your electron,

your human materials will oscillate. So if emitted signals are same pace, means like same information, same exactly same information will be constructive interference, means like your signal will be amplitude. That's why your intensities are high. But sometimes your interaction is out of pace. It's not same pace, will be destructive interference, means like your peaks are,

For example, the decrease or the disappear. So this depends on the interference. This one has inflammation. And then depression. Depression is very important. So here you try your crystal structure, right? Astral defraction, molecular defraction.

you have to have a diffraction. What is diffraction? Transmission means that your excited beams are penetrated. Right? Penetrate means actually you measure absorption spectrum. It's not measure absorption because you measure transmitters. Or you're, for example, if you transmitted your photon energy and then you input, you know input energy, you measure output. Then, this is to measure the transmittance of your central.

Then you can compare input energy and output energy. That difference is maybe somehow observed from the user. That's why from transmission, you can measure absorption. Reflection, reflection, you know. Reflection, reflection, reflection is also in optics. Okay, so put up all the factors of what you have

the data optics mirror or filter or something, this portion, or we use something photon energy. So reflection, reflection of phenomena is very important because, so that's why we have to know and scattering, or polarization. Even though you guys already know, what is this? This one we have to have some understanding of phenomena, so a little bit.

Or carefully think about those kinds of interferences, how you affect your region. And also reflective index. Definition of refractive index is very much important. So all these phenomena, physical phenomena, interference, diffraction, absorption, emission, scattering chloroidation or dispersion, we utilize

basic origin of your instrument analysis. So the same phenomena with like, for example, XRD or the electron reflection, UV-Vis, or some KIA, LAMA, or polarized microscope, some convocal microscope, something like this. So always with your proof interaction happening with something, this physical phenomena,

You measure instrument. This is neutralized, simplified, so this is electromagnetic. Mediation, right? So as you can see, with this relationship, we can select different energy, means like the internal frequency have interaction, which I call nuclear speed transition or electric speed transition, or molecular,

So vibration, rotation, or the column relating to the wall. In this case, for example, you want to bend again. Then your electron excites from the conduction band to the valence band. You need to have high energy. So in that case you can utilize high energy. Then you can understand the transition between your valence band to conduction band. If you want to just transition between your different shaft, K-share, L-share, M-share, then we don't need to high energy.

You have to have a little bit, it's already enough to stimulate those kind of energy. Then you need to some lower FTR region, where you actually have to do it. And then X-cancer or X-ray spectroscopy. So this is information. This is you have to find. What kind of information? You want to know just some chemical environment, or just simply some atoms near,

What kind of environment you have to utilize proper energy and then specifically, if you want some molecular structure, then if you want some organic synthesis or some organic with some organic material surface chemistry, surface-leganic exchange, then with animal spectroscopy you can understand some dividing between some organic or some organic-organic, some coupling,

some molecular structure, or you can utilize understanding from an NMR spectroscopy. That's why, for the research people, an NMR spectroscopy is a basic instrument to understand the eometrics. Or micro-evolution, then this is ESRI. Because normally, in this case, you can understand some unpaired electric skin, electrons,

or some radical species, for example you use something binding, some organic stuff, if you want some more kind. Then you can measure some ESR, or higher spectroscopy, or UG, the peer spectroscopy you can understand in the intrinsic, the lateral structure. More detail, this is the slide you already know.

So, if you utilize some electromagnetic radiation, I try simply, this is dual, right? It's wave length or the photon. But in this case, propagates some light, there are some electric field and magnetic field perpendicularly to oscillate, right? How much speed? Because electronic and magnetic field propagate - Okay.

Speed of light, you can simply just calculate Maxwell equation. If you calculate this electric field oscillation and magnetic field oscillation, you can actually propagate with the speed of light. 3.8, second point.

So anyway, this one, electromagnetic radiation is propagated with electric field and magnetic field is perpendicular to the speed of light. So in this case, for example, again, I will explain the details about the electron microscope because electron microscope utilizes probe-energized electrons. Accelerated electrons cannot utilize the electron microscope.

optics, just glass optics. So if you utilize some SDM or TM, this is the energy's electron beam. Electron beams cannot utilize for glass optics. That's why electron microscope utilize magnetic lens. So this is how. Simply, in this case, if you change the electric field, then this is activated electron beam. If you increase the electric field,

and then your amplited magnetic field. That's why this one, if you simply change the electric field, you can change the magnetic field. That's why you can make magnetic range for electron microscope. This is the origin of your electron microscope. So, I read, or spray, or detail later. Anyway, you have to make sure this is

radiation have your nature, wave and then particle. So now we have to know what kind of interaction between your light source and what is the diffraction, transmission, refraction, scattering, polarization, maybe sometimes, not always utilize but some specific, more detailed understanding of your

The prompt is you have to, for example, simply polarisation. This is, for example, if you do some spectroscopy related work, this polarisation interaction is very much important. Anyway, let's take a look. What is the meaning? Again, just remember, you already know this is wave function. What is the wavelength? What is the amplitude? What is the intensity?

So always energy related with weight loss. And then, characterized by amplitude, for frequency weight loss. So always you got the spectroscopic intensity proportional to the amplitude, square of amplitude. And this intensity related constructive interference of your wave function. So here.

So amplitude and the wavelength, the frequency and period. So here, one thing. So wavelength means that normally we measure scale, it's nanometer, sometimes centimeter scale. Normally wavelength is nanometer, for example, 500 nanometer or 600 nanometer visual range. But if you measure more, higher wavelength, which is important,

20,000 nanometer or 40,000 nanometer is not easy. So in that case, you can utilize wave number. For example, wave number means like inverse wave length. So LTI spectroscopy or Ragnar spectroscopy normally utilize longer, longer wave length. In that case, normally x-axis energy will be wave number, inverse centimeter or inverse number.

This one, because wave number is higher means your wave max is low. So always you have to easily translate Relaturation with energy, wave number, and wave max. Frequency. Relaturation with frequency. So frequency is normally a heart, right? Or the inverse set, right? And then, first we can put the varicade of appropriation.

This one is related to refractive. So you have to know definition of refractive index. Refractive index means that your interference will be, a little bit more.

So, we let the magnet take. Make it this intense, this, . Amplitude, the square weight.

- So?

If you want to measure something, bending, understanding of your bending head, you have to find a transition between your balance bend to conduction bend, or the momentum to normal. So, means you have to emit, recite your energy higher than bending. So, this way you can understand the transition. If you want some energy of your certain atoms,

or different transition related energy or something energy related vibration. For example, you want to do something molecular species, there are six-bond or single-bond or double-bond with different different number of binding, you need to have higher energy to vibrate. So all kinds of vibration or transition related energy

So, this is why your photon energy related something transition means absorption, emission, related phenomena, interaction you can get. Because, in some cases, sometimes more difficult to overlap with something transition or something energy is similar. Energy you cannot easily distinguish. In that case, you need to alternative analysis.

For example, in some cases your energy is overlapping with something different, overlapping interaction, then somehow you have to alternative method to distinguish, or you have to increase resolution of your instrument. Then you can distinguish clearly, but no way. It's not clearly distinguished, it's no way. Anyhow, so always

particle-related behavior. We measure energy. So, always, again here, simple equation convert. If you have a wave length, you can immediately calculate energy. But, related wave length, energy, this is simple relation. If you convert, this one is energy 3.5. If you try something,

stimulate something to know that is 780 nanometer. Maybe this energy, the wavelength is limited to this much energy. For example, if you measure some photomereal spectroscopy, peak position was 780 nanometer. Then simply you can not reject the number, but you can estimate all my samples band gap is about 1.6 electron volt. You can calculate.

you can estimate. So energy is proportional to frequency wave number and energy is inversely proportional to wave rays. If you try to put energy related, then you have to understand the relationship. Now let's take a look at something basic.

phenomena from the reflection. So reflection is, you know, the varices. But reflection is very important in spectroscopy because this reflect, reflection phenomena we utilize always the spectroscopy, you just travel past where you can guide it.

Reflection is simply in the elementary school, right? Reflection means your input energy, output energy is the same direction. Reflection means bending. Reflection means your instant angle, the outer angles are different. But somehow here, this is the same.

depression is an angle of instant and that. Depression angles are safe. This is elementary, but you have to have understanding. This is a simple equation because depression is like, you normally use the problem, air to reflect with some glass. Glass, because always the pressure phenomena you have to have interference with different Refractivity is medium. So, simply,

We can refraction the rate, we can calculate, for example, different medium, refractive index, for example, this is medium, for example, add air, because the new instant waves are from the air to reflect with glass. Maybe air and the glass are reflected in the C-D block. So simply from this simplification,

For example, if you instantly eject the light, only 4% light reflect. Other light can be transmitted. Right? Transmit. So, to the top part, for example, air to the glass, glass to air, only maximum 8% your instant light can be reflected. This one cannot utilize for your spectroscope.

Because if your beams are present this way, then you want to go over the right, can be 90 degree, reflect, the beams you want to interact without any energy loss. That means almost perfect, more than 95, 200% of your instant beams have to reflect with your pathway. Otherwise, always you know the natural, your instant beam intensity.

And then measurement is reflected. Right? So always compare input energy, output energy. This is somehow our measurement. So, reflection. Normally materialized glass, most of the inside spectroscopy there are so many glass or the reflector or some filter inside. So, even though only 8% light can be reflected, then you cannot utilize. So that's why,

Always, if you coating on the glass, metal coating glass, always more than 95%, almost 95% your incident beams will be reflected. Because if you coating with metal, there are so many letters, right? So, amplitude. That's why when you do, if you are the interesting wavelength range, there are so many different kinds of work.

For example, UV-inheced aluminum, this is aluminum coated some glass or silver or gold. So depends on your measurement related to some near-air range or visual range and UV range, you can select proper, correct mirror. Otherwise, in this case, 250 nanometer to 450 nanometer, if you try this one,

almost 90% light can be reflected. Or in this case, for example, your interest rate is 750 to one micro. Then there are different kinds of a mirror you can find out. So you have to find correct, for example, simply, if you want to measure some, your period of thickness, this is a related refractor. So, this case,

your exact, for example, your instant view, you have to know, otherwise your period sequence measurements are some artifacts. So anyway, you have to hide out the pressure, and this is maybe, maybe I do not have to know your material. This is the simple equation. And move that shot.

Normally, a snare slow, maybe you might hurt. So, a snare slow means, so your reflection means like bending. So bending is a different wave-like energy. Bending, bendings are different. But most probably related to the reflective effects of your video. For example, a snare slow means, for example, your instant beam and then the bending is from the normal. from the normal.

Then this angle to the reflected angle. So this is the input and this is the output. And the reflective index and the reflective index. What happens simply if you just put the in air to water or in air to glass or in air to some color, always two mediums are reflective indexed. It's different, right? So means your light is not the straightforward. So we'll be bending, right?

depends on refractive index of your medium. So, space flow means N1, sine setter equals N2, sine setter. So, for example, if you know refractive index of your medium, normally L, and then incident angle, if you know. Then, if you know, for example, the refractive index of your medium, then you can calculate how much the right will be bending.

This is the relationship. So, reflective index is the simple equation. The relation between speed of light in vacuum and medium. The relationship. So, as you can see here, vacuum, water, air, water, some glass, or culture glass, just glass, The refractive index is different. So typically,

Also, this refractive index is related with the thickness of your medium. So for example, if you want some glow box and then you want to put this light inside the glow box, then this light, for example, if you align the height of your incident beam, then actually the inside glow box, outside through this glass will be this height is not the same height.

So if you align with the same height, then always your light will be something wrong. The recitation, right? So you have to estimate how much reflection will be happening with the different refractive index. So this is a refractive index. Direct constant of refractive index. So you have to careful, typically spectroscopy. Just take a look. And then transmission.

The definition is light as smooth, but clear to your heart. What just means, to transmit as normally transmission and militarized measurement, absorption spectroscopy, IR spectroscopy, neutralized transmission related treatment. Because you input energy and then something absorption from the U medium or the middle sample, and then you measure the output. So input energy to output energy, so the interaction between your output energy to your medium happening, right? So,

This one also simply the relationship between absorption and corruption and then this is proper. So normally when you measure intense or neoabsorption spectroscopy, IR spectroscopy related, absorption to corruption means like this is observance and then concentration related. So you might

Remember, and also I will tell you later, absorption spectroscopy because simply you have absorption. Absorption means like your transmission. So this absorption spectroscopy, absorption related, your absorption coefficient, and then concentration of your medium, your central, and then L means like travel distance. In case period,

In case solution can be, you might consider. And also maybe in your transmission, for example, simply your sample inside tube-end, put them in solution and dispersion in your sample. Or simply with glass or a silicone substrate and you deposit your sample, can be different environment. you have to consider when you measure insolution,

In the pillow, your measurement has to have different weight. Same of social spectrum, but you have to have the more carefully characterized in subversional pillow. I will explain later. And the dispersion, this dispersion means like you try to read different wavelengths, different differential angle. So that's why normally white line You can.

distinguish with different wavelength because depends on the wavelength, your diffraction angles are changed, right? That's why if you slow the prism, you can separate with different wavelength, different energies. So that's why when you trace spectrous conclusion to UVB or FTIR,

range, you can, through the separation of your energy, you can utilize specific wavelength range as proof. Or your signal also goes into wavelength different dependence. Then when you measure detector, you have to separate with this wavelength. So even though your of your high five.

When you measure detector, always deflection, related, you know, deflection, related, relationship you have to know. And this one also, the deflective index depends on the wavelength, right? Whenever the refractive index is low, the wavelength is high, it's like relationship. Other than the scattering, so this one also,

Just simply, in elastic you can see, elastic, scattering, there are no energy change. So this one is no energy change. And in elastic scattering, it's normally neutralized some other spectros, here also same. Also scattering phenomena is related to electron.

Here also there are elastic and inelastic. So even though in this case normally in the elastic, scatterings are always related to the core, inside core, of your core. And inelastic, scatterings are related to some of the energy change, right? So this pyramid will be utilized for measurement. So just take a look, what is elastic? For inelastic, you can easily

can understand. But I will detail this frame later with some electron microscope. Because this phenomena we can utilize some secondary electron microscope, EDX spectroscopy, or you can understand the backscattered electron microscope, something like this. We try some phenomena. Electron beam and inelastic scattering, or random spectroscopy,

FTIR spectroscopy utilized for this type. In eliciting, scattering. I will explain later in real instruments. Just take a look at this one. And another important, diffraction phenomena. Because the diffraction phenomena is always being utilized for some defined - I saw the sculpture. - Actually, the first shot,

for electron deflection, we try to phenomena. But in case possible, you might know, so Hanzenberg uncertainty, principle, you might take course. This one, relationship between so position and momentum. Also energy, time, relationship is the same Because the principle means

You cannot exactly know, say, simultaneously you cannot know the position of a momentum. Because in this case, your medium is very small than your momentum. Actually, the momentum energy is higher. So this is a relation. For example, delta energy to delta time. Because always, if you measure spectroscopy, your carriers will have the right time. So always they have relationship, energy and time. Your lifetime is smaller.

Then your energy will be high. Energy high means weight length is low. Something like your carrier dynamics or your impurity or something, the interaction phenomena is origin related some, we don't need to more detail understand, but at least anyhow, our measurement always, interaction. There is something meaningful.

phenomena. Physical phenomena we utilize for measurement. So anyway, depression, phenomena is you might know, break-flow and lambda equal to this sign setup. This is normally whatever you don't understand the meaning of break-flow, but every most of our Most students know

equation. L lambda equals two distance and center. Means here also you have to see each d, center to lambda. This is energy, your input energy. And then this is different angle related. This is interplane distance. Interplanar distance. This is crystal information. So you know the input energy, your x-ray energy.

Your electron beam energy, then if you see that, and then depends on the, your, this is position, right? If your small pipe or small slit, will be more strong, if that phenomena will be happening, right? If your energy is much smaller than this something, then your, your, something interpronar distance or something impurity.

is higher, smaller than your energy, that never gonna happen. In depression, then you cannot get any information. So anyhow, this one, depression simplification is very slow, then relationship, your energy, and then different angle, and then this is D space. Means if you know D space, then you can understand your

the plane, plane plane interaction information. If you have something multiple peak or multiple spectrum, the depression or the pattern or the depression spectrum, then you might, that is again, related interference. So this one, simply this is the interference, means, for example, if you instant means are pain-to-face something with the slip slip.

Then there are two slits will be, even though this is parallel light, will be more, because if you're kind of small, the slit will be more higher, higher momentum light, will be more diffracted. This is way, right? Then if you penetrate two slits, will be, again, this way will be diffracted. Then you can find out because

Because in this case, for example, some current is intensely high, or some current is intensely slow, or nothing. But normally, our crystal structure is purely. Even though there are a little bit of some defect or impurity, but basically, mother crystal structures are always belongs to seven crystals, 14-grabits lattice. means like symmetry, purity.

So your defective pattern or the spectrum will be purity. So that's why if you instant your electron beam or some x-ray beam will be interaction, diffraction and interaction, then you can get something. So in this case, you have to know, constructive interference means the same pace or same freestyle plane will be same pace means that diffraction

signal will be amplitude, means amplitude, increase. So in this case, say phase of wave will be constructive interference. However, if your phase are out of phase, will be destructive interference. Means like these phase are disappear. So in this case we measure this one even though

We measure some depraction pattern image or X-ray spectrum will be depends on your depraction with something plane or something structure will be you can measure from here. So if you measure image then depraction pattern image. If you measure some spectrum, pattern X-ray spectrum, right? You make it. Because this...

And the result is your instant x-ray beam, electron beam, your depends on the interaction. With your crystal structure, will be short. That's why this is . So more detail, number detail. But always, this is typical single clip star. Electron, the interaction pattern, Normally this is the center because this is,

most probably your electron beam. And then each this spot will be related. Your electron beams are distracted with your crystal structure. So each this spot has information of your crystal structure, plane information. So later I will show, because as you can see here, this spot, some crystal structure, This is what related to the old phrase

from 2 to 0 flame, this one 1 to 0 flame, and then in this case, why 1 to 0 is much brighter than 2 to 0 because your most probably 1 to 0 flame, your instant electron beams are more diffracted because this means like more constructive interference than this one. So simply if you compare to this one and this one, this one is intensely high.

If you convert the spectrum, maybe this one, for example, your X-ray spectrum is one, two to zero, one-on-one plane, is the intensity 100%. Two to zero, maybe it's 20%, something. You can see, right? So, this information is exactly the same as your X-ray, deep pressure, right? Because this spot, your spectrum, Related to your body,

So, constructive interference or disruptive interference is simply related. Simply, this is passive interference. For example, constructive interference, for example, your personal equilibrium is that this is a strong, high intensity, related, and under.

Wavelength, pathway differences with one wavelength will be constructive interference. In this case, amplitude. Destructive interference, in this case, hot or lambda. In this case, for example, dark spot. Because here, this is, for example, strong. This is bright field or dark field. But this one is always related to crystal structure, purity.

So this is the front field and the front field is always purely because this will be distance. Your lattice constant will be the same. So your defective planes are always purely. If you see something, in this case, if you see something other, depression, some spot, or then this one will be your impurity related defective. So the problem is:

If there is something defect related to the deflection, then this is the mother crystal structure. If you define defect related deflection, always there is a relationship. For example, you might know that many materials are sometimes used to be infuriating. And generally there are so many defects, for example dislocation or twin or some point defect, something like this.

the TM deflection, you can distinguish. For example, the dislocation of the tweed, what is the relationship between your material, the precept structure with defect-related orientation or something, relationship we can understand from electron deflection. That's why you need to know. That's simple measure. But anyhow, here, just remember, constructive interference or destructive interference relationship

Even maple eggs or half-veil eggs remain, especially because these are destructive or constructive. I'll show later more detail in TM. Because I'm not talking about XRD because XRD we have a specific natural program, But always make sure

X-ray deprecation and electron deprecation, but always correlated. Polarization. Maybe this one is a little bit sophisticated. Typically measurement, I think most of the cases, you do not utilize the polarization. But if you work some spectroscopy or your materials are isocropic because your planes are different.

different kind of environment, then when you measure some measurement, you have to have some polarized light, not the universal light. Because universal lights are simply, you can't just measure the intensity, how much is thrown, intensity, whatever. But always, our, your light has some direction, right? So if you try polarization of your light, because

In this case, simply, personally. So, normally you can utilize white light. This light is unpolarized, non-polarized. Okay, just, but if you utilize polarizer, simply there are different kinds of polarizer. Because in this case, if you put down something polarizer, then you can penetrate some, your unpolarized light, You can make something polarized unit.

linear colloid light you can utilize. So that colloid light has information, direction information. Most of the problem you utilize this is white light. But if you want something more detailed understanding about the direction related phenomena, you have to have, you have to utilize the polarizer. Because this polarizer depends on your polarizer. Your unparallized is always you can make some of the

I'm not talking about the details, but anyhow, just take a look at the polarization. Maybe later in spectroscopy, I will mention the polarization, why this one is important. If you take a look, because we utilize the light, how about actually with this light, it oscillates with the electron.

of your materials. So this electron also can generate some diper. Diper means you can separate with the core, plus charge and then negative charge. Then you can make some progenyation. So those kinds of interactions you can utilize spectroscopy in many cases. Isotroping materials are, which are the same response in all directions, but unisolating materials are,

direction, dependent response. So somehow your materials, your phenomena is related to something. Typically your materials are unisotropic materials. Then typically if you measure just a white line, then just compared collectively, not quantitatively. In this case, if you utilize a chloroid unit, the light, chloroid light,

Then you can understand it some direction dependent response. For example, the Rama spectroscopy, you know the graphene is a layered structure, but you know the layer by layer or inflate. Something, what you can see, you can see. So in this case we have to utilize some polarized light to this thing more detail. Oh, you checked me?

or some other spectroscopy is important. So take a look at the concept. So typically, polarization. Why polarization of light is important in material analysis? This polarization, normally the Y0, T, and energy. So this is, as you can see, the vacuum commutative activity, and then this one is the source of commutative.

So, it depends on this one. This polarization is high or low with this one, electro susceptibility. So, this one means sensitivity of the electronic structure. So, normally, these parameters are related, direction dependent. So, this one is large, then, for example, this one is strong polarization or high defective index or some strong

absorption, if this is small, then the electron barely moves under some electric means like light, or weak polarization or low reflective index, or some low weak optical signal. So this is also related to polarization. Just take a look. So if you measure some,

2D materials, strain, or some composite. Like for example, in organic solar cell, if you can the polymer to different isotope structure, it's important to trace some of the radiation of the Earth. And these are risky because these are the, simply I just put down the electron,

Metainteraction means you are in this previous system, normally photon energy, but we utilize electron beam with your SEL, TL, always interaction with your indices, indices indices electron beam. So you have to understand the phenomena of interaction with your medium and electron beam. And X-ray defection or X-pens, you utilize some X-ray beam with your both-fills on interaction.

So this one is when I start some experience with the electron microscope. Again, I will explain later. And this is I already mentioned. So, again, just take a look. What material characterization is, what is this? This is always we have a question. What kind of information?

What kind of energy you have to utilize? How can 3T, how can 3T sample? This is amazing, but most important. And also you have to know, always measurements are comprehensive. Before 3T, after 3T, or something. You change some parameters, and then these parameters somehow you want to advance. You want to put the, improve something.

So these differences affect your device or some new materials. So what are we really doing? And then the signal will be intensely change or line is change, broadening, whatever. Because right, scrutiny or shiftness in this change is all.

meaning of your interaction, right? So this is most probably from changing of your peak or broadness, that is information, right? That is information. So these differences are, again, you're trying to not try to combine, define, quantitative, quantitative. This is last slide, was that correct? When you get

spectrum always scale because most of the measurements you get this kind of spectrum but you have to make sure when you writing the manuscript when you read some some some the paper if you get something data this data have to clear because if you see this data something they talk you have to understand what is the literature was it in this case

Typically, x-axis is your parameter, your input energy. And then y-axis is our result, intensity. So always you have to careful scale up. Because wave length means people know wave length. Nanoliter, right? Sometimes you create a wave number, inverse is an inverse nanometer.

Or, this is parameter. You change the different wavelengths, you got something in this observance. This one is with different wavelengths, this one is with the observance. So, in this case, this one has no observance. This energy is smaller than the band band. And this technique is something very strong, choppy. This is intense.

And broadness, these differences, because from here to here, normally half-fuel is half-maximal, right? Full is half-maximal. In this case, pure spectrum, full spectrum, right? Gaussian distribution. But some cases, if these spectrums are not Gaussian distribution, then you might think about why this side and this side is different. Because most probably there is something pain,

related to some defect or something. So always you have to make sure this is parametric, what you change and what you get. And then this is absolute scale or relative scale and normal scale, arbitrary scale, but you don't know the exact definition. Because sometimes some paper showing intensity A dot U dot. This is arbitrary unit.

and put the number. Because generally arbitrary unit means here. Arbitrary unit means what? Measurement absolute value cannot be obtained because this is not absolute value. So if you put the arbitrary unit, you don't need to put this number. Because the input number means that this is absolute value. Absolute value. So in this case, this will be long because if you try intestine A dot U dot,

Then this is not absolute value. So if you put down this number, it looks like this is absolute something number. Obsolver, in this, 0.4, 0.2, 0.1.2 means this is the observance and then there are no any, arbitrary unit scale parts. This means that this result, this is absolute value because this energy is 600,

Looks like these samples are exactly 0.3 something observance. This observance related concentration. So this is absolute value. Real value. So if you try the absolute value, always have to be careful because this absolute value means like this is real value. Real information. So you have to have carefully calibration. This is really intrinsic number or this absolute value contains some architect.

So in this case, absolute bell scale risk, you have to exactly put down exact number, how much. In this case, for example, if something changed, 0.4 to 1.2 increase, then you can calculate the quantitatively you can tell. So how much percent? We do something treatment. This is absolutely. But many cases, for example, in this case,

There are two ways. In this case, intensity is relative. Or in this case, always put in the exact condition. Which means intensity, not absolute value, but this way is relative. Relative means just comparison with reference to you got different environment, right? And this is normalized, two maximum. Means like this intensity,

simply normalize with the highest, maximum value. So when you put down your paper, your results, you have to clearly distinguish, you put down absolute value, or arbitrary unit, or you have to put this data, you have to do a negative comparison. In this case, your intensity are like you just manipulate, normalize with the maximum peak.

Because why you will need, in this case, this one is same data. Same data. But in terms of your direction of view, right? Because in this case, if you get this is low data, you plot them. But there are two information. Because intensity change and wave matching. Because if you change the time, because this one is original, right? You know what I mean? And then we decrease whatever measurement condition. This peak wave places slightly measured.

So these peaks are spectrums of two information. Intense change, very redshift. But you cannot clearly compare. So simply relative means without any comparison, just compare low data. So you can say with increased time, whatever treated time or measurable time, these peaks are decreased and then other redshifted. How much redshifted comes from here to here, here to here, here to here, here to here? Maybe you explain.

People cannot clearly see how much regulates are shifted. So in this case, just normalize with this maximum peak, then all the peaks are same intensity. So in this case, normalize peaks are only you can see. In this case, exactly you can see with time, you can see how much regulates are

How much we will see it. So, whenever you are in the fleet, you result, sometimes you are just showing absolute value, or just relative, or sometimes lowline. This work you have set long, you have to exactly have to show you what kind of energy. Maybe sometimes you measure some binary change,

This is binding everything. How much should it? And this is always the intensity. Intensity means amplitude is secure. Right? Right is always wave. So this wave is, Intensity change means like your interaction is constructive interference. Right? Custructive interference. You have to interpret. But if you put this one,

normalize intensity and then you say with different time, your intensity whatever, you cannot say. Only in this case, you can say weight length or something with condition changing how much. So from here to here, if you know the exact number, at least you can say how much. 59, which is the number? 59 will change. 59 will change why?

is why 15-arm change means your extreme condition can be affected. Something changes. So that means you have to explain. Otherwise, if you lose, pull it down, okay, I change something, parameters, I make different material. Either I measure different reaction time or different measurement time, the peak position was,

From here to here, change. This is not science, right? You have to find out meaning. Why? With this parameter, change. This one. This meanings are what kind of interaction. Surface-related, defect-related, band-bondiode-related, whatever. Meanings are exactly you have to explain. But in this case, if you have this measurement, you cannot clearly demonstrate. Then you have to find out

That phenomenon, what kind of earth-proof energy can prove? This one. That's why your experiment, this is the main experiment, and then your, maybe you wrote paper. This is the main phenomenon. But I have additional experiment, blah blah blah, really support this phenomenon clearly. That physical meaning is what? This says, but you don't just--

Just your science is not making the number of data, because always in many cases, the number of data always in many cases is garbage. So good students not generate many data sets, because good students always define clearly what kind of energy you have to utilize, what kind of phenomena have affect you this one, if you clearly explain,

No doubt. Everyone can accept. Then you don't need to audition or experiment. Right? You don't need to audition. So you have to minimize. Experiment in characterization as much as you have to minimize. Then you have to find out the paper. Even when you do the power needle for your experiment, you don't need to make so many experiments. Just do that.

Just a proper way. That's it. So next week we'll start on the optical microscope. Very simple but trying to allow you can try this optical microscope.