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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Does a list of errata for Ashcroft and Mermin's Solid State Physics exist?

I have tried Googling a list of errata for A&M, but it does not seem to exist. Has anyone found one?
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334 views

What is the Difference Between BCS Theory and Ginzburg-Landau Theory?

What is the Difference Between BCS Theory and Ginzburg-Landau Theory? I have been studying Superconductivity and I know that Both of the theories (BCS Theory and Ginzburg-Landau Theory) can be used ...
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66 views

Hole, solid state physics

In n-type semi conductor, when hole is created, which starts to move, but not in p-type semi conductor, hence, is a hole a static or dynamic? hole is absence on electron, absence means nothing, then, ...
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54 views

Exciton in semi-conductor

I don't understand why an exciton describes only the interaction between an electron hole and an electron in the conduction band? How is this interaction different from the interaction between an ...
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1answer
83 views

Hamiltonian for electron hole

I found in lectures notes that the Hamiltonian containing the energy of a electron hole without any interaction is given by $$H = \sum_k d_k^{\dagger} d_k \left( \frac{\hbar k^2}{2m_V} - E_{0,V} ...
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67 views

Bloch's theorem for Semi-Infinite Lattice

If we have a lattice Hamiltonian $$ \sum_{n'\in\mathbb{Z}}H_{n,n'}\psi_{n'} = E\psi_{n} \,\forall n\in\mathbb{Z} $$ such that $ H_{n,n'} = H_{n+q,n'+q}$ for some $q\in\mathbb{N}$ and for all ...
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42 views

Two state Hubbard modell

I am given the two state Hamiltonian $$ H = U \sum_{j \in \{L,R\}} n_{j \uparrow}n_{j \downarrow} - t \sum_{\sigma \in \{\uparrow,\downarrow\}}(a_{L \sigma}^{\dagger}a_{R \sigma} +a_{R ...
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539 views

Horrifying electron gas model

I am given the Hamiltonian, in an exercise called plasmons, and where $\langle, \rangle $ denotes the expectation value. $$ H = \sum_{k} \varepsilon_k a_k^{\dagger} a_k + \sum_{k_1,k_2,q} V_q ...
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153 views

Coordinate system for crystallographic groups

In the International Tables for Crystallography for each crystallographic group an asymmetric unit is supplied (mathematicians call this a fundamental domain of the group). This region is a bounded ...
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86 views

Why are (most) solids periodic?

Is there a rigorous proof that periodic arrangements minimize the energy of a group of particles?
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151 views

Origin of High-temperature Superconductivity

What is the mechanism that causes certain materials to exhibit superconductivity at temperatures much higher than around 25 kelvin?
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63 views

Symmetry breaking and band gaps?

Can the discontinuity in the E-K dispersion relation of a periodic lattice (at the boundary of a Brillouin zone) be understood as a consequence of breaking continuous translation symmetry into ...
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How is potential energy actually stored in a steel spring at the atomic level?

Elasticity is one the most intriguing phenomena, wiki gives a summary explanation of what happens in a steel spring: the atomic lattice changes size and shape when forces are applied (energy is ...
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1answer
59 views

How to discretize a finite crystal?

I am trying to find a general method to discretize a finite crystal system. How I have been discretizing systems so far (using Wannier functions): When you have an infinite crystal, you may apply ...
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0answers
66 views

Why does Pressure Increase the Tc (Critical Temperature) of a Superconductor?

Just a heads up - please make this answer understandable to around 1st year degree level physics - not PhD research. So I can understand it - thanks. I was wondering why they Critical Temperature ...
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1answer
94 views

Why isn't doped silicon a strongly correlated electron system?

Most books on strongly correlated electrons claim that when the number of itinerant electrons is small and the screening length is large, that the system becomes "strongly correlated", (i.e. the ...
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28 views

Binding forces in crystalline solids

I am referring to rocks in this instance. Individual crystals grow together in an igneous rock as it solidifies. I know that the SiO4 tetrahedron is the basic building unit of silicate minerals, and ...
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4answers
470 views

How does current flow in superconductors if Cooper pairs have zero momentum?

I've been reading a lot of condensed matter textbooks, which state both that the net momentum of a Cooper pair in a superconductor is zero, and that Cooper pairs have momentum when they carry current. ...
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42 views

intervalley optical phonon scattering

Is there any difference between modeling of intravalley and intervalley optical phonon scattering in solid?
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1answer
118 views

How corner atom of a cube is shared by 8 atoms? [closed]

Since each atom is at the corner of a cube and 8 cubes meet at each corner. Therefore each atom is shared by 8 cubes. But I don't visualize it, so please tell how I Visualize it.
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191 views

How do I derive the eigenvalues of the 1D Heisenberg model? (Bethe Ansatz)

I've been trying to work through Introduction to the Bethe Ansatz I (by Michael Karbach and Gerhard Muller) in spare time and I am having trouble deriving the eigenvalues given in equation (5) for ...
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164 views

Real part of the AC conductivity has a discrete spectrum => What physics?

If the real part of the AC conductivity $\text{Re}[\sigma(\omega)]$ has a discrete spectrum only, i.e., $\text{Re}[\sigma(\omega)]=a_1\delta(\omega-\omega_1)+a_2\delta(\omega-\omega_2)+\cdots,$ what ...
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114 views

Why don't electrons simply diffuse back when illuminating a photodiode?

Assuming you connect the cathode and the anode with a conductor (no sources), why can't the electron-hole pairs created by the photons diffuse back instead of going through the wire? My reasoning is ...
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60 views

Crystal lattices in solid state

I found this problem in Christman's book fundamental of solid state physics What is the Miller index for a plane parallel to both $3\vec{a}+\vec{c}$ and $\vec{b}$, in any lattice?
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35 views

Screened potential of charged impurity in a 2-dimentional electron gas

What's the analytical relation of screened potential of charged impurity in a 2-dimentional electron gas?
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1answer
390 views

Time reversal operator in tight-binding model with second quantization form

In the tight binding model, $H=\sum_{r,r'}ta^{\dagger}_{r}a_{r'}+h.c.$. When conducting a time reversal transformation, what form will this Hamiltonian take? Or how can I express time reversal ...
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133 views

Influence of applied voltage to an electron of a metal

I would like to ask what would happen to the potential well of an electron being trapped in a metal? If I apply a voltage trying to accelerate the electron out of the potential well. Would It make the ...
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636 views

To what extent can the superconducting order parameter be thought of as a macroscopic wavefunction?

I know that the order parameter does not obey the Schrodinger equation; it instead obeys the Ginzburg-Landau equation. However, I am unclear as to the situations under which the view of the ...
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1answer
313 views

The Debye temperature for diamond

To simplify the calculation, let's assume that the average speed of sound in the diamond is simply $v_s=\sqrt{E/\rho}\simeq1.414\times10^4 \ \text{m/s}$, and the Debye frequency $$\omega_D=v_s\left( ...
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1answer
134 views

Folding of wave-vector in Band Theory of Metals

In the Kronig-Penney model in the Band Theory of Metals, we derive the energy levels as function of wave vector as shown in the figure. But my professor showed that we represent the levels folded ...
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38 views

Why do electrons form Cooper pairs below certain temperature? [duplicate]

Just a heads up - please make this answer understandable to around 1st year degree level physics - not PhD research. So I can understand it - thanks. 1) In solid state physics, why is it that below a ...
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39 views

Discrepancy in introducing Schottky barrier

I have a problem regarding introduction of Schottky barrier in metal-semiconductor junction. Because of this barrier the energies of conduction band vary discontinuously and hence the potential is ...
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759 views

The reciprocal lattice of HCP lattice

There is a very similar question here Reciprocal Lattice of a non-bravais lattice, but I don't fully understand the answer, and the question is now obsolete so I feel that I should ask it again. How ...
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1answer
189 views

Help needed to understand the dispersion curve of a 1D lattice with diatomic basis

I am trying to understand the dispersion curve (as shown below) of a 1D lattice with diatomic basis. Here are my questions: Can both optical and acoustic branch of phonon simultaneously exist in ...
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151 views

Wannier Hamiltonian in Momentum Space

In connection to a previous question, We can write the one-particle Hamiltonian in the Wannier basis working on a general vector $v$ as : $$ \langle\vec{R},\,\lambda|\hat{H}|v\rangle = ...
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218 views

Wannier Functions as Discrete Basis

In solid state physics, using Bloch's theorem we know that the one-electron energy eigen-function can be written as $\psi_{\lambda,\vec{k}}(\vec{r})$ where $\lambda$ indexes eigenvalues of $\hat{H}$ ...
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269 views

Why doesn't topological phase transition break any symmetry? Hidden symmetry?

This question may be superficial. However why all people saying this without a proof? Just like the "hidden variables" assumption in quantum mechanics, can one disproof that there is no hidden ...
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54 views

Real materials described by the fermionic Hubbard model?

I was always curios what real material are described by the fermionic Hubbard model. $$H = \sum_{\left< i, j\right> \sigma} t_{ij} c^{\dagger}_{i, \sigma} c_{j, \sigma} + \sum_i U_i ...
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210 views

How to compute matsubara frequency summation over computer?

Matsubara frequency sum usually takes the following form: $S_\eta = \frac{1}{\beta}\sum_{i\omega_n} g(i\omega_n).$ But in my problem, $g(i\omega_n)$ is a lengthy expression, which can not be ...
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26 views

Proton energy distribution after Si layer

I've been using SRIM to get an approximation of the energy distribution that a beam of monoenergetic incident ions will have after a thin layer of silicon. However, for my purposes it would be better ...
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52 views

How to understand the unitary? [closed]

In the page 219 of Mahan's Many Particle Physics(3ed), there exists a transform $$ S=c^{\dagger}c\sum_q\frac{M_q}{\omega_q}(a_q^{\dagger}-a_q)$$ In order to prove that the transformation relating to ...
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2answers
724 views

What's the difference between hopping and tunneling?

My professor made a distinction between electron hopping (the closest wikipedia had an article on) and tunneling, saying that one (he didn't say which, but I assume hopping) was temperature dependent ...
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1answer
121 views

A problem about solving energy bands by the method of second quantization

In hopping model, we can get the Hamitonian as $H_0=-t\sum a^\dagger_ia_{i'}$. Then we take the fourier transform and put the operator which are in momentum space in the Hamitonian above. However, I ...
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2answers
91 views

Potential Energy in solids: Why are different equations used for deriving lattice constants and for deriving the properties of phonons?

While deriving the equilibrium lattice constants we use expressions for potential like Lennard-Jones potential which have 6th and 12th order terms or Madelung energy for ionic crystals. While ...
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What is the the real world interpretation of the high dimensionality of quasicrystals?

One of the examples of the problems of 5-fold symmetry is that pentagons tiled on a 2D plane do not completely fill that plane, leaving voids. This may be solved by "folding" it into 3D space, and ...
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1answer
196 views

Can you explain why crystals form without thermodynamics?

I know that the basic reason that solid crystals form is because it's the lowest energy configuration (i.e. this). I am looking for an intuitive explanation for this process, one that does not involve ...
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2answers
317 views

Why are most ferromagnets metals while antiferromagnets are insulators?

This seems to be experimentally true, but I don't quite have an intuition as to why. In the Ising model, we usually consider an insulating ferromagnet if $J>0$, where $J$ is the exchange coupling. ...
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35 views

Symmetry of amorphous thin films

I'm wondering whether amorphous thin films have point group symmetries? Landau's Statistical Physics Vol. I writes: The highest symmetry is that of isotropic bodies (bodies whose properties are the ...
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1answer
144 views

Electron density in metals at non zero temperature

When computing the electron density in metals, the usual crude result is computed for zero temperature. That is, we integrate \begin{equation} n=\frac{8\sqrt{2}\pi m^{3/2}}{h^{3}} ...
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116 views

Why aren't base-centered orthorhombic Bravais lattice simple monoclinic?

I am learning 7 crystal systems and 32 Bravais lattices. I am quite confused about why a base-centered orthorhombic Bravais lattice is not a simple monoclinic one, if we take two edges and a half ...