Zobrazeno 1 - 10
of 195
pro vyhledávání: '"82D55"'
We introduce a multi-band BCS free energy functional and prove that for a multi-band superconductor the effect of inter-band coupling can only increase the critical temperature, irrespective of its attractive or repulsive nature and its strength. Fur
Externí odkaz:
http://arxiv.org/abs/2409.17297
The dispersionless limit of the standard Eliashberg theory of superconductivity is studied. The effective electron-electron interactions are mediated by Einstein phonons of frequency $\Omega>0$, equipped with electron-phonon coupling strength $\lambd
Externí odkaz:
http://arxiv.org/abs/2409.02121
The standard Eliashberg theory of superconductivity is studied. The effective electron-electron interactions are mediated by dispersive phonons, with Eliashberg spectral function $\alpha^2 F(\omega)\geq 0$ that is $\propto\omega^2$ for small $\omega>
Externí odkaz:
http://arxiv.org/abs/2409.00532
Using the recent reformulation for the Eliashberg theory of superconductivity in terms of a classical interacting Bloch spin chain model, rigorous upper and lower bounds on the critical temperature $T_c$ are obtained for the $\gamma$ model -- a versi
Externí odkaz:
http://arxiv.org/abs/2409.00533
Autor:
Roos, Barbara
Since BCS theory of superconductivity is non-linear, it is difficult to study superconducting properties analytically. There is a more tractable linear criterion which determines a temperature $T_l$ below which the system is superconducting. Here, we
Externí odkaz:
http://arxiv.org/abs/2407.00796
We consider the BCS energy gap $\Xi(T)$ (essentially given by $\Xi(T) \approx \Delta(T, \sqrt\mu)$, the BCS order parameter) at all temperatures $0 \le T \le T_c$ up to the critical one, $T_c$, and show that, in the limit of weak coupling, the ratio
Externí odkaz:
http://arxiv.org/abs/2312.11310
Autor:
Roos, Barbara, Seiringer, Robert
We consider the critical temperature for superconductivity, defined via the linear BCS equation. We prove that at weak coupling the critical temperature for a sample confined to a quadrant in two dimensions is strictly larger than the one for a half-
Externí odkaz:
http://arxiv.org/abs/2308.07115
Autor:
Roos, Barbara, Seiringer, Robert
We study the BCS critical temperature on half-spaces in dimensions $d=1,2,3$ with Dirichlet or Neumann boundary conditions. We prove that the critical temperature on a half-space is strictly higher than on $\mathbb{R}^d$, at least at weak coupling in
Externí odkaz:
http://arxiv.org/abs/2306.05824
We argue that the formation of Yu-Shiba-Rusinov excitations in proximitized thin films is largely mediated by a type of Andreev-bound state named after de Gennes and Saint James. This is shown by studying an experimentally motivated model and computi
Externí odkaz:
http://arxiv.org/abs/2304.14448
The interfacial coupling between electrons and magnons in adjacent layers can mediate an attractive electron-electron interaction and induce superconductivity. We consider magic-angle twisted bilayer graphene sandwiched between two ferromagnetic insu
Externí odkaz:
http://arxiv.org/abs/2301.07909