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The reason that space group is not considered by Altland and Zirnbauer is that they were interested in the implication of the symmetries for transport properties of disordered electrons, and once you …

After Fourier transform you get an equation $\displaystyle (E-\frac{k^2}{m})\alpha_{\vec{k}}=\sum_{\vec{k}'}V_{\vec{k}\vec{k}'}\alpha_{\vec{k}'}$ Here $V_{\vec{k}\vec{k}'}\sim \int \mathrm{d} \vec{r …

Let $|\psi\rangle$ be an eigenstate of $H$ with eigenvalue $E$. $\lambda$ is an external parameter that $H$ depends on. In your case it is $\Delta\phi$. Then $$ \dfrac{\partial}{\partial\lambda} \lan …

I don't know much about the AdS/CFT stuff, but the statements about the Kondo effect and superconductivity are rather straightforward: 1) The classical setting for the Kondo effect is an impurity spin … The Ginzburg-Landau level means that the superconductivity is directly described by a charge-$2e$ scalar field, the order parameter, ignoring the electronic origin. …

In either cases the bulk is superconducting. I don't understand why you ask whether it is p-wave or Cooper pair. In this context, "p-wave" always means p-wave pairing, so always a superconductor to be …

.}$ Diagonalizing the Hamiltonian, the spectrum is given by $E_p=\pm\sqrt{\Delta^2+(p^2/2m-\mu)^2}\pm V_z$ If one naively applies the Pfaffian criteria for topological superconductivity, one still finds …

Indeed, it is true that one can find a unitary $U$ to relate $a$ to $c$. To find this unitary, it is most convenient to write everything in the Majorana basis: $c_i=\frac{1}{2}(\chi_i+i\eta_i)$, where …

If we define $\mathcal{T}=i\sigma_y K$ where $K$ is complex conjugation, i.e. $\mathcal{T}\psi_\uparrow \mathcal{T}^{-1}=\psi_\downarrow, \mathcal{T}\psi_\downarrow \mathcal{T}^{-1}=-\psi_\uparrow$, …

It is useful to first review the physics of a quantum planar rotor. Consider the Hilbert space spanned by $|N\rangle$. They are eigenstates of the number operator $\hat{N}|{N}\rangle=N|{N}\rangle$. Th …

When you diagonalize $H_\text{BdG}$, you find the eigenvalues and the eigenvectors. Let us assemble these (column) vectors into a unitary matrix $U$ (this is always possible since $H_\text{BdG}$ is He …

You should forget about the name "Majorana fermions", although people have been using it (unfortunately) a lot in the literature on topological superconductivity. …

Chiral $p$-wave superconductor and He A phase can be considered being equivalent phases of matter, for the following reason: The fact that the superconductor is charged does not make too much differen …

There is no fundamental difference between the signatures found in the two works (Kouwenhoven and Yazdani). Both are tunneling spectroscopy, which roughly measures whether there is a zero-energy singl …

The transmon and Cooper pair box share the same design, but operate in opposite limits: Cooper pair box is operated under the condition $E_C\gg E_J$, so the charging energy dominates. While for transm …

BCS theory deals with superconductivity in a metal, or basically a finite density of non-interacting fermions. …