Related papers: BCS Superconductivity with Fixed Number Parity
The understanding of an electron gas with short coherence length pairs formed by an attractive interaction is believed to be one of the major keys to our theoretical knowledge of the high-T_c-superconductors. Mainly the deviations of the…
We examine possibility of enhancement of superconductive critical temperature in two-dimensions. The weak coupling BCS theory is applied, especially when the Fermi level is near the edges of the electronic bands. The attractive interaction…
We revisit the issue of superconductivity at the quantum-critical point (QCP) between a 2D paramagnet and a spin-density-wave metal with ordering momentum (\pi,\pi). This problem is highly non-trivial because the system at criticality…
We study finite-temperature properties of a two-dimensional superfluid made of ultracold alkali-metal atoms in the BCS-BEC crossover. We investigate the region below the critical temperature $T_{BKT}$ of the Berezinskii-Kosterlitz-Thouless…
We calculate the number and energy densities of a quasi-2D Bose-Einstein gas constrained within a thin region of infinite extent but of finite width d. The BEC critical transition temperature then becomes an explicit function of d. We use…
The remarkable robustness of high-temperature superconductors against disorder remains a controversial obstacle towards the elucidation of their pairing state. Indeed, experiments report a weak suppression rate of the transition temperature…
By means of the Lanczos method we analyze superconducting correlations in ultrasmall grains at fixed particle number. We compute the ground state properties and the excitation gap of the pairing Hamiltonian as a function of the level…
Near a two-dimensional Ising-type nematic quantum critical point, the quantum fluctuations of the nematic order parameter are coupled to the electrons, leading to non-Fermi liquid behavior and unconventional superconductivity. The interplay…
We study the specific heat of a model supercooled liquid confined in a spherical cavity with amorphous boundary conditions. We find the equilibrium specific heat has a cavity-size-dependent peak as a function of temperature. The cavity…
The BCS-BEC crossover realized experimentally with ultra-cold Fermi gases may be considered as one of the important scientific achievements occurred during the last several years. The flexibility for operating on these systems on the…
We contrast {\it four} distinct versions of the BCS-Bose statistical crossover theory according to the form assumed for the electron-number equation that accompanies the BCS gap equation. The four versions correspond to explicitly…
The low-temperature specific heat (SH) of overdoped La_{2-x}Sr_{x}CuO_{4} single crystals (0.178=<x=<0.290) has been measured. For the superconducting samples (0.178=<x=<0.238), the derived gap values (without any adjusting parameters)…
Ever since BCS theory was first formulated it was recognized that a large electronic density of states at the Fermi level was beneficial to enhancing $T_c$. The A15 compounds and the high temperature cuprate materials both have had an…
We investigate the ground state properties of a disordered superfluid Fermi gas across the BCS-BEC (Bose Einstein condensate) crossover. We show that, for weak disorder, both the depletion of the condensate fraction of pairs and the normal…
In this work, a question is tackled concerning the formation of a superconducting condensate in an earlier proposed model of "elastic jelly", in which phonons of the ion system play the part of initiating ones. It was shown that in…
A model, based on classical mechanics and thermodynamics and valid for \textit{all} superconductors, is devised to investigate the properties of the \textit{current-driven}, superconducting to normal transition. This process is shown to be…
We study a mesoscopic superconducting ring threaded by a magnetic flux when the single particle level spacing is not negligible. It is shown that, for a superconducting ring with even parity, the behavior of persistent current is equivalent…
We consider the current correlation function for a three-dimensional system of fermions embedded in a homogeneous background and mutually interacting via an attractive short-range potential, below the (superconducting) critical temperature.…
Bose-Einstein condensation (BEC) of an ideal gas is investigated, beyond the thermodynamic limit, for a finite number $N$ of particles trapped in a generic three-dimensional power-law potential. We derive an analytical expression for the…
We develop a systematic theoretical approach to incorporate the effects of a static white-noise disorder into the BCS-BEC crossover near the critical temperature ($T_c$) of the superfluid transition. Starting from a functional-integral…