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Related papers: Cooper pairing reexamined

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We study a two-component Bose gas with a symmetric spin-orbit coupling, and find that two atoms can form a bound state with any intra- or inter-species scattering length. Consequently, in the dilute limit, the Bardeen-Cooper-Shrieffer (BCS)…

Quantum Gases · Physics 2017-10-02 Dekun Luo , Lan Yin

We have demonstrated that it is possible to access a crossover scenario starting with a weak coupling (BCS) d-wave superconductor to a strongly coupled Bose-Einstein condensate (BEC) phase as the exchange interaction is tuned in a two…

Strongly Correlated Electrons · Physics 2015-06-15 Subrat Kumar Das , Ayan Khan , Saurabh Basu

We use a symmetry-constrained variational procedure to construct a generalization of BCS to include Cooper pairs with non-zero momentum and angular momentum. The resulting gap equations are solved at zero and finite temperature, and the…

Superconductivity · Physics 2008-11-26 Yang Sun , Mike Guidry , Cheng-Li Wu

We experimentally determined various thermodynamic quantities of interacting two-component fermions at the zero-temperature limit from the Bardeen-Cooper-Schrieffer (BCS) region to the unitarity limit. The obtained results are very accurate…

The simplest, algebraic quantum-electrodynamical corrections, due to the double-negative energy subspace and instantaneous interactions, are computed to the no-pair energy of two-spin-1/2-fermion systems. Numerical results are reported for…

Chemical Physics · Physics 2025-12-09 Péter Jeszenszki , Edit Mátyus

The BCS theory models electron correlations with pure zero-momentum pairs. Here we consider a family of pairing Hamiltonians, where the electron correlations are modelled with pure arbitrary-momentum pairs. We find all models in the family…

Superconductivity · Physics 2017-07-12 Lian-Ao Wu

We study mesoscopic pairing in the one dimensional repulsive Hubbard model and its interplay with the BCS model in the canonical ensemble. The key tool is comparing the Bethe ansatz equations of the two models in the limit of small Coulomb…

Strongly Correlated Electrons · Physics 2007-05-23 Luigi Amico , Andrea Mastellone , Andreas Osterloh

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…

Bose-Einstein condensation (BEC) in two dimensions (2D) (e.g., to describe the quasi-2D cuprates) is suggested as the possible mechanism widely believed to underlie superconductivity in general. A crucial role is played by nonzero…

Superconductivity · Physics 2016-08-15 S. K. Adhikari , M. Casas , A. Puente , A. Rigo , M. Fortes , M. A. Solís , M. de Llano , A. A. Valladares , O. Rojo

Although BCS pairs of fermions are known not to obey Bose-Einstein (BE) commutation relations nor BE statistics, we show how Cooper pairs (CPs), whether the simple original ones or the CPs recently generalized in a many-body Bethe-Salpeter…

Superconductivity · Physics 2009-11-10 M. de Llano , F. J. Sevilla , S. Tapia

In this study, the pairing mechanism for layered HTS materials based on attraction between electrons from adjacent layers is proposed. Initially, each layer has expanded Fermi sphere owing to ridged geometry. When the two layers are close…

Superconductivity · Physics 2011-09-20 A. Tavkhelidze

The Hamiltonian and trial function in the BCS theory are improved to test the limit of this theory. The Cooper pairs arise from standing electron waves, ready to move with atoms, giving high Tc. The Hamiltonian is derived from alternating…

Superconductivity · Physics 2007-05-23 X. H. Zheng

As a model which displays a picture of the symmetry energy as an energy of rotation in isospace of a Cooper pair condensate, a Hamiltonian with a pairing force and an interaction of isospins is analyzed in the Hartree-Bogolyubov (HB) plus…

Nuclear Theory · Physics 2009-10-29 K. Neergård

We derive upper and lower bounds on the critical temperature $T_c$ and the energy gap $\Xi$ (at zero temperature) for the BCS gap equation, describing spin 1/2 fermions interacting via a local two-body interaction potential $\lambda V(x)$.…

Superconductivity · Physics 2009-11-13 Christian Hainzl , Robert Seiringer

The superconductor niobium possesses a narrow, roughly half-filled energy band with Bloch functions which can be unitarily transformed into optimally localized spin-dependent Wannier functions belonging to a double-valued representation of…

Superconductivity · Physics 2007-05-23 Ekkehard Krüger

In this study, the possible pairing mechanism based on attraction between electrons from adjacent CuO2 layers is proposed. Initially, each CuO2 layer was found to expand the Fermi sphere owing to ridged geometry. When the two layers are…

Superconductivity · Physics 2010-10-05 Avto Tavkhelidze

Electrons in a multielectron bubble in helium form a spherical, two-dimensional system coupled to the ripplons at the bubble surface. The electron-ripplon coupling, known to lead to polaronic effects, is shown to give rise also to Cooper…

Superconductivity · Physics 2007-05-23 J. Tempere , V. N. Gladilin , I. F. Silvera , J. T. Devreese

Strong evidence for pairing and superfluidity has recently been found in atomic Fermi gases at the BCS-BEC crossover both in collective modes and RF excitation energies. It is argued that the scale for the effective pairing gaps measured in…

Superconductivity · Physics 2009-11-10 H. Heiselberg

Pair density waves (PDWs) are superconducting states formed by ``Cooper pairs" of electrons containing a non-zero center-of-mass momentum. They are characterized by a spatially modulated order parameter and may occur in a variety of…

We report the effects on the thermodynamic properties of a 3D Bose gas caused by a temperature dependent energy gap between the ground state and the first excited state of the energy spectrum of the particles constituting the Bose gas which…

Superconductivity · Physics 2026-01-13 Juan José Valencia Acevedo , Miguel Ángel Solís Atala