Solid-state physics studies how macroscopic properties of solids (mechanical, electrical, optical, etc.) result from their microscopic structure. It usually deals with the scale where quantum properties of the particles are substantial.
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Why electrons are relativistic in Graphene and non relativistic in vacuum?
If a free region in space has a potential difference of one volt, an electron in this region will acquire kinetic energy of 1 eV. Its speed will be much smaller than the speed of light hence it will ...
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1answer
117 views
Working with atomic (?) units in solid state physics
I'm having some troubles understanding the units used in solid state physics paper. In the paper I read
$\Lambda a \sim 1$
where $\Lambda$ is a momentum cutoff and $a$ is the lattice spacing of a ...
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0answers
164 views
Electron Fermi gas
My question is about 2-dimensional Fermi gas of electrons.
What is magnetic susceptibility when $T<<T_F$ (where $T_F$ is Fermi Temperature)
and,
What is the ratio between Pauli and Curie ...
5
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1answer
406 views
Yet another question on the Lindhard function
Here's another question concerning the Lindhard function as used in the physical description of metals.
First we define the general Lindhard function in the Random Phase approximation as
...
5
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1answer
187 views
Question concerning the Lindhard function
I'm having a question concerning the Lindhard function.
The reference I'm using is the standard text "Quantum Theory of Solids" by Charles Kittel.
I'm concerned with Chapter 6, subchapter "Method of ...
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0answers
367 views
On what does the breakdown voltage of zener diode depend on [closed]
On what factor does the breakdown voltage of zener diode depends
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1answer
174 views
Nonlinear absorption coefficient and the band gap
How does the nonlinear absorption coefficient depend on the band gap?
How can that coefficient be calculated theoretically? (Preferably with an example)
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1answer
344 views
Possibility of Bose-Einstein condensation in low dimensions
I remember having a problem (for practice preliminary exams at UC Berkeley) to prove that Bose-Einstein condensation(BEC) is not possible in two dimensions (as opposed to three dimensions):
For ...
4
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0answers
126 views
What happens to a Luttinger liquid under time reversal?
Suppose you a have an ordinary Luttinger liquid with
$$ H = \int dx \sum _{\eta= \pm 1 , \sigma =\uparrow,\downarrow } \psi^\dagger_{\eta, \sigma} (x) (-i v \eta \partial _x) \psi _{\eta,\sigma} (x). ...
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6answers
2k views
What are “electron holes” in semiconductors?
I'm tutoring senior high school students. So far I've explained them the concepts of atomic structure (Bohr's model & Quantum mechanical model) very clearly. Now the next topic to be taught is ...
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2answers
205 views
4 digit Miller Index for a cubic structure?
As the title states, can a Miller index for a cubic structure have 4 digits? If I have a structure with intercepts (2,8,3) on the x-y-z axes respectively, the following Miller index would be (12,3,8), ...
3
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1answer
303 views
How does thermal broadening of the Fermi Function cause electron coherence loss?
Generally, there are two ways for electrons to lose their wave-like properties in a solid material. One is by way of collisions that cause changes in the energy and momentum of the electron. The other ...
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3answers
402 views
Indirect band gap semiconductor for LEDs?
Can someone please explain why Indirect band gap semiconductor can not be used for LED creation. Can you also please give me some reference link for details.
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0answers
65 views
How to calculate 2D soft-body Physics [duplicate]
Possible Duplicate:
2d soft body physics mathematics
The definition of rigid body in Box2d is
A chunk of matter that is so strong
that the distance between any two bits
of matter on ...
3
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4answers
354 views
Why does the density of states in a solid scale as $\sqrt{E}$?
In three dimensions, the density of states of a free electron is the square root of the energy of the electron. Can somebody explain the relationship between this dependence and the shape/formation of ...
0
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1answer
78 views
References for the source and application of bonding-antibonding splitting on electronic structure?
I am currently doing research on semiconductor materials, so I need a very strong background in band theory to understand the literature. I am currently trying to understand the relationship between ...
3
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2answers
534 views
Propagation of light in transparent media: absorption and reemission or scattering?
In the two Phys.SE questions What is the mechanism behind the slowdown of light/photons in a transparent medium? and Why glass is transparent? transparent media were discussed. But I'd like to clarify ...
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1answer
443 views
Importance of Kohn anomaly? [closed]
What is practical importance of Kohn anomaly for experimentalists and/or theorists?
2
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1answer
172 views
Fourier analysis in crystallography
What is the best reference for an introduction to the use of Fourier analysis in crystallography?
3
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1answer
240 views
Lorentz invariance of a frequency- and wavelength- dependent dielectric tensor
Suppose we have a material described by a dielectric tensor $\bar{\epsilon}$. In frequency domain, this tensor depends on the wave frequency $\omega$ and the wave vector $\vec{k}$.
Clearly not all ...
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0answers
166 views
Any interesting physics theroies/equations to be used in a video game? [closed]
I am designing a little game based on Newtons Graviational Law.
Are there any theories that I can use to create games?
thanks
3
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1answer
117 views
Repulsive classical identical particles on a square lattice
I am not sure whether it is some well-known named model in statistical physics.
I could not find it in any standard text-book that I know of.
Let there be $N$ identical classical particles ...
2
votes
3answers
266 views
About symmetry, and about electron density in crystals in particular
The book Introduction to Solid State Physics by Kittel says:
"We have seen that a crystal is invariant under any translation of the form T [...]. Any local physical property of the crystal, such as ...
6
votes
1answer
328 views
Number density of LO and LA phonons as a function of temperature?
I'd like to know the how the number density of longitudinal optical (LO) and longitudinal acoustic (LA) phonons varies as a function of temperature of the material. Is there a simple expression for ...
6
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2answers
3k views
How can the Hall effect ever show positive charge carriers?
The Hall effect can be used to determine the sign of the charge carriers, as a positive particle drifting along the wire and a negative particle drifting the other direction get deflected the same (as ...
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0answers
135 views
What does plasmon look like in 3D band structure graph?
Consider metal, and its reciprocal lattice representation with Fermi surface.
What is the correct way to represent a plasmon in this system? M.b. rotating points on the surface? Or 3d membrane-like ...
3
votes
2answers
511 views
bandgaps for 2D square lattice with potential of the form V=V(x) + V(y) - what are the general properties?
Let us consider Bloch wave function solutions for a particle confined to a 2D square lattice with a potential of the form
$V=V(x) + V(y)$
(that is, one that can be factorized).
In this case we can ...
2
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4answers
959 views
how to find the effective mass of a hole
how can we find out the effective mass of a hole,since a hole in the valence band is just an absence of electron?
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0answers
370 views
Evaluation of band gap from transmittance
How can I evaluate the band gap of my ZnO thin film.
Thickness=d=80 nm
I’m aware of alpha=-1/d*log(T)
But I can’t fit a line to my data.
And: How can I smoothen my data on about 346 nm?
Do you have ...
5
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1answer
458 views
When is use of the 'effective mass' concept appropriate?
In textbooks the characteristic length scale of an exciton, or an electron bound to dopant atom, in silicon is calculated by analogy to the vacuum case.
Bohr radius in vacuum:
$$a_0 = \frac{4 \pi ...
5
votes
3answers
211 views
Mobile “muonic hydrogen”
If we look at the atomic positions in a single crystal sample with a diamond like lattice, there exist directions along which there are long hexagonal "tubes" (I'm not sure if these have a proper ...
3
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2answers
537 views
Madelung constant list (for surfaces as well)
Searching for this on google proved to be quite tedious, but I reckon that someone working with crystals a lot might know this off the top of his head:
Is there a good source that lists the Madelung ...
3
votes
1answer
367 views
Nature of tetragonal distortion in Jahn-Teller effect
I am wondering: If I have a regular octahedron as my starting point, oriented along the x-y-z axis, and now Jahn-Teller suggest I elongate or compress along the $z$-axis, what happens along the other ...
5
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4answers
2k views
Chemical potential
This is something probably very basic but I was led back to this issue while listening to a recent seminar by Allan Adams on holographic superconductors. He seemed very worried to have a theory at ...
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1answer
575 views
Effective mass in Aluminium lattice?
How do we calculate the effective mass of an electron in an Aluminium lattice? Is there any simple analytical way to work it out?
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3answers
321 views
Are we crystals?
Can we say that we are crystals because just like crystals we are made up of very small unit (cell) making up almost the same shape (our body) everywhere.
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0answers
285 views
Fermi level in disordered amorphous and/or organic semiconductors
So, the Fermi level in crystals is pretty easy to understand. Been using it and talking about it in terms of the highest occupied level forever. However, I'm now reading about disordered systems. A ...
7
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3answers
293 views
If I take a handful of salt and wait for an infinite time will it become a single crystal?
That pretty much says it.
Suppose I have some powder of $NaCl$. It is kept in contact with itself in vacuum. You are free to remove all the disturbances that bother you.
Is that true that, well, ...
3
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1answer
279 views
What is the boundary condition of graphene flake with zigzag edges?
It is a question about free carrier behavior in graphene flakes. (or may be called charge confinement)
Say if we have a perfect hexagonal free standing graphene flake terminated with zigzag edges. ...
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votes
3answers
2k views
What is Fermi surface and why is this concept so useful in metals research?
Particularly, I can somewhat appriciate the Fermi energy idea - the radius of Fermi surface which is a sphere. But is there any quantitative use of more complicated Fermi surfaces?
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1answer
879 views
Graphene and Klein bottle?
I am trying to understand graphene as a topological insulator.
The spin orbital interaction in graphene is very small (~10mK?). But if we consider that, then graphene should be a topological ...
11
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3answers
986 views
How Non-abelian anyons arise in solid-state systems?
Recently it has been studied non-abelian anyons in some solid-state systems. These states are being studied for the creation and manipulation of qubits in quantum computing.
But, how these ...
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1answer
317 views
How metallic surfaces states can emerge in topological insulators?
Topological insulators are materials known to have bulk insulator and metallic surface states. But, what is the origin of these metallic surface states? And how the topology of band could help the ...
5
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2answers
2k views
The Spectral Function in Many-Body Physics and its Relation to Quasiparticles
recently, I stumbled accross a concept which might be very helpful understanding quasiparticles and effective theories (and might shed light on an the question How to calculate the properties of ...
3
votes
2answers
298 views
Scattering of phonons and electrons within solids
I got a question concerning the scattering of phonons and electrons.
I read an introductory explanation to this process that is somehow
not very satisfactory. It goes like this:
Let $\psi_{k}$ and ...
4
votes
1answer
1k views
What is injection level (semiconductor physics)?
I am currently reading journal articles about semiconductor physics in solar cells. What is injection level?
I'll try to start off with what I understand. Photons hitting the silicon cause its ...
6
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2answers
423 views
Quantum numbers and the band structure of solids
I got a question concerning the band strucutre of solids.
The reference I'm using is the book on solid state physics by Ashcroft/Mermin.
My problem is that I don't completely understand the reason ...
5
votes
1answer
444 views
How to calculate the properties of Photon-Quasiparticles
in recent questions like "How are classical optics phenomena explained in QED (Snell's law)?" and "Do photons gain mass when they travel through glass?" we could learn something about effective ...
12
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3answers
562 views
Shine a light into a superconductor
A type-I superconductor can expel almost all magnetic flux (below some critical value $H_c$) from its interior when superconducting. Light as we know is an electromagnetic wave. So what would happen ...
3
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1answer
182 views
Experimental samples with rare earth metal
Many experiments, such as optical, superconductivity, etc, use the samples that involve rare earth metals and transition metals. Why are they used that often. Is the main reasons:
They have the ...
