We’re rewarding the question askers & reputations are being recalculated! Read more.

Questions tagged [optical-materials]

The tag has no usage guidance.

42 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
4
votes
0answers
39 views

Difference between permittivities eps-opt and eps-inf?

Very often in materials physics we are interested in the relative permittivity at optical frequencies, which is usually denoted by $\varepsilon_\text{opt}$ or $\varepsilon_\infty$. But I'm confused ...
3
votes
0answers
77 views

Identifying diagrams for optical processes

I was reading some papers on the study of the optical properties of some metals and came upon these conference proceedings by Hopfield from 1972. They are on the study of the infrared properties of ...
3
votes
0answers
171 views

optical scattering cross section and polarization tensor

The optical scattering and absorption cross sections are well known to be $$ C_{sca} = \frac{k^4}{6\pi}|\alpha|^2 \qquad C_{abs} = k\Im (\alpha) $$ where $k$ is the wavevector and $\alpha$ is the ...
3
votes
0answers
188 views

Are there Optical Magnetic Mirrors (OMMs) which reflect via interaction with the magnetic field?

The most familiar mirror relies on reflection from a metal, where the very strong interaction of the electric field component of the EM wave with the conduction electrons produces a reflected wave. ...
2
votes
1answer
80 views

Is there a material that allows light to pass perpendicular to the surface, but reflects at an angle?

This is inspired by Michael Steven's new video about optics. He shows off Selenite, which has the property that light entering on one side travels perpendicularly down the crystal until it exits the ...
2
votes
0answers
45 views

How to decide between sizes of particles for maximum light intensity for scintillation?

Are nanoparticles or microparticles or quantum dots better suited as scintillation materials as far as light yield intensity is concerned? I was unable to find literature that compares micro vs ...
2
votes
0answers
583 views

Bandwidth-length product of an optical fiber

A multimode step index fiber has a numerical aperture of 0.2 and a core refractive index of 1.47 . Estimate the bandwidth-length product for the fiber assuming only intermodal dispersion when: (a)...
1
vote
1answer
41 views

Classical (non-quantum) explanation for the transparency of glass?

Is there a classical explanation for the transparency of glass? How did physicists explain the transparency of glass before quantum mechanics?
1
vote
0answers
22 views

Reflection coefficient phase using Kramers Kronig, formula equivalence

Why are the following two formulas for the phase of the reflection coefficient equivalent (according e.g. to [1])? \begin{align} \Theta(\omega_0) & = - \frac{\omega_0}{\pi}P\int_{0}^{\infty}\frac{...
1
vote
1answer
24 views

Dielectric properties of polarizing beam splitter

Are all polarizing beam splitters made up of dielectric materials?If so, what kind of dielectric materials are actually used to make them?
1
vote
0answers
32 views

What is a Material Called that Translates the Image of a Touching Object's Surface?

What is the name of a material that moves light through it in such a way that it appears that the surface of an object has translated through the material? Also, what is an example of this type of ...
1
vote
2answers
499 views

Is there a way to make infrared pass through metals?

I am curious to know a way that will make infrared pass through metals. Metals are good reflectors of infrared,can we manipulate the wave in order to make them pass through metals?.
1
vote
0answers
159 views

Change of refractive index using semiconductor

I was wondering, if it is possible to change the refractive index of a semiconductor using an electric field or current? I have heard about injecting charges to tune the refractive index. How/Why does ...
1
vote
0answers
73 views

How can an optical signal be transduced to an audio/mechanical signal without using electricity?

There are several ways to directly convert acoustic/mechanic signals into optic signals (e.g. opening/closing a shutter, or the acousto-optic effect). Is there any way to do the reverse, without using ...
1
vote
0answers
38 views

Reconcile the principle axes, crystallographic axes, and some global axis for a polycrystalline uniaxial birefringent elastooptic material

I'm trying to work out the tensorial algebra for elastooptic effects in a uniaxially birefringent material that has a polycrystalline grain structure. Let's denote a global reference frame $\{x,y,z\}$....
1
vote
0answers
53 views

Mode distribution and Phase constant for nonlinear optical fiber

While going through the derivation of Nonlinear Schrodingers equation from the Helmholtz equation I came across the following two pdes, $\nabla_\perp^2 F + \left[ \epsilon\left(\omega\right) k_0^2 - \...
1
vote
1answer
92 views

473 nm light through a single mode fiber designed to operate between 1500 and 1600 nm

Can we send light with 473 nm through a single mode fiber designed to operate between 1500 to 1600 nm spectrum? The radius of the fiber core is 4.25 micrometer, NA=0.12 and the single-mode cut-off is ...
1
vote
0answers
518 views

About Powell lens

I am a Post graduation student and I am doing a project on the conversion of a Gaussian beam into a flat top beam using optical components. I have found that the best component to do the same is a ...
1
vote
0answers
55 views

What is the principle behind the use of one LASER for optical pumping of Rubidium in presence of magnetic field?

How can we use a single LASER for optical pumping of rubidium in the presence of magnetic field as the zeeman levels are degenerate in the presence of magnetic field and how to decide upon the ...
1
vote
0answers
82 views

Twisted Nematic liquid crystal: extent of degradation due to DC drive?

It is commonly accepted wisdom that a Twisted Nematic LCD must always be driven using AC instead of DC, because DC will supposedly denature the LC. I have two questions: Does this effect only happen ...
0
votes
1answer
27 views

Does diffraction depend on refractive index of a medium?

Does diffraction pattern depend on refractive index of a medium? Does the transmitting media influence on difraction the phenomenon or is it caused by light and the edge alone? Is a diffraction ...
0
votes
0answers
10 views

Question about adjusting focus on augmented reality

I am working on a project and I am trying to build augmented reality glasses. I have a question about focusing the projection from screen and the real object on the far distance at the same time. How ...
0
votes
1answer
52 views

What is the physics behind Samsung Galaxy Axx-series “3D Glasstic”?

How does back cover of Samsung Galaxy A30 transform light into those wavy white lines? I hope you could draw a schema of incident and reflected light with the answers.
0
votes
0answers
46 views

Need an IR transmitting plastic that is white in color and partially opaque to visible light?

I need an IR transmitting plastic material (85% or better) that is white in color, but partially opaque to visible light. Does anyone know of such a substance?
0
votes
0answers
15 views

Why does the images of slit slip down in bottom as we move the lens?

Why does the images of slit slip down in bottom as we move the convex lens in the experiment of "determination of wavelength of sodium light by fresnel biprism experiment". We made the system coaxial ...
0
votes
0answers
31 views

How I can add lenses stacked on front of iphone camera to increase magnifying power?

How we can stack different lenses to increase magnifiying power of a smartphone camera? Is there any way to test if stacked lenses will focus light on image sensor of smartphone exactly right before ...
0
votes
0answers
35 views

Polarizing Beam splitter

What could be the effect of aging in Polarizing Beam Splitters? Is it possible that the Axes for s-polarization and p-polarization change due to some environmental effects on a polarizing beam ...
0
votes
0answers
32 views

For the high-frequency permittivity of a material, do I need to look beyond its value in the optical energies region?

I was trying to find $\varepsilon_\infty$ for InSb, and the value I found on Kittel p. 416 was 15.6. But in the literature, even at 6 eV, $\varepsilon (\omega )$ is still in the negative (at -3.835) ...
0
votes
0answers
9 views

Why the first ring's radius appears to be too little in newton's ring experiment?

In newton's ring experiment we should be going to see a large number of rings with their converging radius. But the ring right next to dark fringe is way nearer than 2nd or 3rd which appears to be an ...
0
votes
0answers
11 views

Semiconductors with low thermal conductivity (lattice matched to GaAs)

What are the semiconductors with lowest thermal conductivity that can be grown on GaAs with the least possible incorporated strain (i.e. lattice-matched or close to it)? GaAs has thermal conductivity ...
0
votes
0answers
101 views

A simple thin-film transmittance calculation problem

I am trying to reproduce results of thin-film transmittance given in this article by using this online thin-film calculator tool (www.filmetrics.com). I would like to use the calculator later for more ...
0
votes
0answers
15 views

Spectrum of Dielectric Function along Energy

What do the peaks and troughs in the spectrum of the dielectric function (real and imaginary parts) along energy indicate? I understand that the real part represents the polarization and the imaginary ...
0
votes
0answers
27 views

How to theoretically determine thermal emissivity of thin polymeric films?

Maybe someone could help with determining gray-body emissivity of thin films such as polyethylene. There is a lot of conflicting data online with some sources stating polyethylene's epsilon value as 0....
0
votes
1answer
42 views

Semireflectivity of a material (acrylic)

I am using acrylic for a project due to its semi-reflectivity (as well as the fact its easily laser cut, and is in great supply where I am). However, I was wondering about the factors that determine ...
0
votes
1answer
363 views

The numerical aperture of optic fibre and angle of incidence

First My college book contains the following passage: the angle of incidence (relative to the fibre axis ) can't be too large else the ray would be refracting on the core\cladding boundary and ...
0
votes
0answers
127 views

Calculation of Phase Delay of a Curved Planar Dielectric Waveguide (i.e., bend)

I am working on a very phase sensitive planar dielectric waveguide device and I need to calculate the phase delay induced by a bend of some radius, $r$ and of $\phi$ radians for a give planar ...
0
votes
1answer
46 views

Material that reflects only a certain polarization?

Do materials exist that (significantly) reflect one polarisation of light and transmit all others?
0
votes
0answers
39 views

Lower Threshold optical beam limiter?

We would like to implement a very fast beam limiting, so far google search shows that the common threshold ranges is in 1J/cm^2 or more, this could take seconds to activate as our laser ranges from 1 ...
0
votes
1answer
76 views

What are the physical optical limitations photonic metamaterials can offer?

Modern technology has introduced new photonic metamaterials that can extend optical properties beyond what standard materials can offer. For example a negative index of refraction is now possible ...
0
votes
1answer
54 views

Why is Al2O3 so popular in plasmonics?

I've tried to find my own solution for this question and found out that It is cheap It is an insulator It efficiently absorbs UV Are there more properties that makes it so popular?
0
votes
0answers
397 views

Where can I find a complete list of metamaterials up to today?

Where might I find a list of all the metamaterials up-to-date?
-1
votes
1answer
59 views

How reflectivity of metals depends on the condition of the surface?

Does it depends on the flatness and pureness of surface. does it change when dust or oxides settle on it.