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Related papers: Universal behavior of the BCS energy gap

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From the viewpoint of operator theory, we deal with the temperature dependence of the solution to the BCS gap equation for superconductivity. When the potential is a positive constant, the BCS gap equation reduces to the simple gap…

Functional Analysis · Mathematics 2013-10-30 Shuji Watanabe

Based on recent progress in mathematical physics, we present a reliable method to analytically solve the linearized BCS gap equation for a large class of finite-range interaction potentials leading to s-wave superconductivity. With this…

Superconductivity · Physics 2019-04-24 Edwin Langmann , Christopher Triola , Alexander V. Balatsky

In the standard theory of superconductivity a quasiparticle excitation changes the energy of the system by the quasiparticle energy. But the number of excitations determine also the gap energy which further determines the energy of the…

Superconductivity · Physics 2014-05-20 Dragos-Victor Anghel , George Alexandru Nemnes

We show that the long-distance behavior of the two-body density correlation functions and the Cooper-pair probability density of a balanced mixture of a two-component Fermi gas at $T = 0$, is universal along the BEC-BCS crossover. Our…

It is proven that there exist some universal relations between the energy gap and the differences of the thermodynamic potential, entropy, specific heat and critical magnetic field for many two- and three-dimensional models of…

Superconductivity · Physics 2015-06-24 R. Gonczarek , M. Krzyzosiak

We deal with the gap function and the thermodynamical potential in the BCS-Bogoliubov theory of superconductivity, where the gap function is a function of the temperature $T$ only. We show that the squared gap function is of class $C^2$ on…

Mathematical Physics · Physics 2010-06-07 Shuji Watanabe

For the Cooper/BCS model interaction in superconductors (SCs) it is shown: a) how BCS-Bose crossover picture transition temperatures Tc, defined self-consistently by both the gap and fermion-number equations, require unphysically large…

Superconductivity · Physics 2007-05-23 M. de Llano , F. J. Sevilla , M. A. Solis , J. J. Valencia

The existence and the uniqueness of the solution to the BCS gap equation of superconductivity is established in previous papers, but the temperature dependence of the solution is not discussed. In this paper, in order to show how the…

Mathematical Physics · Physics 2011-07-08 Shuji Watanabe

The (mean field based) BCS theory is considered one of the most successful theories in condensed matter physics. It is justified in ordinary metal superconductors the coherence length $\xi$ is large, with two important features: the order…

Superconductivity · Physics 2018-01-22 Qijin Chen

One of long-standing problems in mathematical studies of superconductivity is to show that the solution to the BCS gap equation is continuous in the temperature. In this paper we address this problem. We regard the BCS gap equation as a…

Mathematical Physics · Physics 2013-09-02 Shuji Watanabe

New calculation reveals that E is constant in a thin layer across the Fermi surface, befitting the definition of energy gap parameter, Delta varies dramatically. The BCS self-consistent equation has a simple and exact solution, showing that…

Superconductivity · Physics 2007-05-23 Xue Heng Zheng

We consider color superconductivity with two flavors of massless quarks which form Cooper pairs with total spin zero. We solve the gap equation for the color-superconducting gap parameter to subleading order in the QCD coupling constant $g$…

Nuclear Theory · Physics 2009-11-07 Qun Wang , Dirk H. Rischke

The Bose-Einstein condensation (BEC) temperature $T_{c}$ of Cooper pairs (CPs) created from a very general interfermion interaction is determined for a {\it linear}, as well as the usual quadratic, energy {\it vs}% center-of-mass momentum…

Superconductivity · Physics 2017-08-23 F. J. Sevilla , M. Grether , M. Fortes , M. de Llano , O. Rojo , M. A. Solís , A. A. Valladares

For a superconductor to be able to receive an external magnetic field, there must be a vacant energy state in the superconductor to receive the energy associated with the field. For a small range of energies near that of the critical…

Superconductivity · Physics 2012-12-04 Ralph C. Dougherty , J. Daniel Kimel

We present a numerically exact solution for the BCS Hamiltonian at any temperature, including the degrees of freedom associated with classical phase, as well as amplitude, fluctuations via a Monte Carlo (MC) integration. This allows for an…

Superconductivity · Physics 2009-11-11 M. Mayr , G. Alvarez , C. Sen , E. Dagotto

We investigate superconductivity in a grand canonical ensemble with {\it fixed number parity} (even or odd). In the low temperature limit we find small corrections to the BCS gap equation and energy spectrum $E(k)$. The even-odd free energy…

Condensed Matter · Physics 2009-10-22 Boldizsar Janko , Anders Smith , Vinay Ambegaokar

The central result of BCS theory are the Universal Ratios which do not depend on physical parameters of the superconductor under study. Several attempts have been made to introduce the van Hove Scenario within BCS theory but in none of them…

Condensed Matter · Physics 2009-10-28 R. Baquero , D. Quesada , C. Trallero-Giner

We study color superconductivity with $N_f=1,2,$ and 3 massless flavors of quarks. We present a general formalism to derive and solve the gap equations for condensation in the even-parity channel. This formalism shows that the leading-order…

Nuclear Theory · Physics 2009-11-07 Andreas Schmitt , Qun Wang , Dirk H. Rischke

We investigate the BCS critical temperature $T_c$ in the high-density limit and derive an asymptotic formula, which strongly depends on the behavior of the interaction potential $V$ on the Fermi-surface. Our results include a rigorous…

Mathematical Physics · Physics 2023-12-21 Joscha Henheik

We consider the linear BCS equation, determining the BCS critical temperature, in the presence of a boundary, where Dirichlet boundary conditions are imposed. In the one-dimensional case with point interactions, we prove that the critical…

Mathematical Physics · Physics 2024-03-27 Christian Hainzl , Barbara Roos , Robert Seiringer