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Related papers: Superconductivity with repulsion: a variational ap…

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We investigate the influence of general forms of disorder on the robustness of superconductivity in multiband materials. Specifically, we consider a general two-band system where the bands arise from an orbital degree of freedom of the…

Superconductivity · Physics 2021-07-13 D. C. Cavanagh , P. M. R. Brydon

We study the subgap Yu-Shiba-Rusinov (YSR) states in the Richardson's model of a superconductor with a magnetic impurity for different electron pairing strengths from the weak-coupling Bardeen-Cooper-Schrieffer (BCS) regime to the…

Superconductivity · Physics 2022-08-31 Rok Žitko , Luka Pavešić

It is generally believed that the laws of thermodynamics govern superconductivity as an equilibrium state of matter. Here we point out that within the conventional BCS-London description of the normal-superconductor transition in the…

Superconductivity · Physics 2016-08-02 J. E. Hirsch

Hund's pairing refers to Cooper pairing generated by onsite interactions that become attractive due to large Hund's exchange $J$. This is possible in multiorbital systems even when all local bare interactions are repulsive, since attraction…

Superconductivity · Physics 2022-09-13 Mercè Roig , Astrid T. Rømer , Andreas Kreisel , P. J. Hirschfeld , Brian M. Andersen

The connection between the supersymmetric quantum mechanics involving two-component eigenfunctions and the stability equation associated with two classical configurations is investigated, and a matrix superpotential is deduced. The issue of…

High Energy Physics - Theory · Physics 2011-07-28 G. S. Dias , E. L. Graça , R. de Lima Rodrigues

Bogoliubov Fermi surfaces are contours of zero-energy excitations that are protected in the superconducting state. Here we show that multiband superconductors with dominant spin singlet, intraband pairing of spin-1/2 electrons can undergo a…

Superconductivity · Physics 2020-01-28 Chandan Setty , Shinibali Bhattacharyya , Yifu Cao , Andreas Kreisel , P. J. Hirschfeld

In many situations a BCS-type superconductor will develop an imbalance between the populations of the holelike and electronlike spectral branches. This imbalance suppresses the gap. It has been noted by Gal'perin et al. [Sov. Phys. JETP 54,…

Superconductivity · Physics 2008-11-15 A. Nahum , E. Bettelheim

We analyze in detail the superconductivity that arises in an extended Hubbard model describing a multiband system with repulsive interactions. We show that virtual interband processes induce an effective attractive interaction for small…

Superconductivity · Physics 2022-07-22 Valentin Crépel , Tommaso Cea , Liang Fu , Francisco Guinea

This work analyses the dynamical properties of periodically-driven band models. Focusing on the case of Bose-Einstein condensates, and using a meanfield approach to treat inter-particle collisions, we identify the origin of dynamical…

Quantum Gases · Physics 2017-05-10 S. Lellouch , M. Bukov , E. Demler , N. Goldman

We present the results of numerical studies of superconductivity and antiferromagnetism in a strongly correlated electron system. To do this we construct a Hubbard model on a lattice of self-consistently embedded multi-site clusters by…

Superconductivity · Physics 2007-05-23 H. Watanabe , S. Doniach

A recently developed theory for the problem of Andreev reflection between a normal metal (N) and a multiband superconductor (MBS) assumes that the incident wave from the normal metal is coherently transmitted through several bands inside…

Superconductivity · Physics 2015-05-14 M. A. N. Araujo , P. D. Sacramento

In this paper we study a model of s-wave marginal Fermi liquid superconductor at two dimensions. Besides the usual Bardeen-Cooper-Schrieffer(BCS) point attractive interaction, the fermions in our system also interact {\em via} a long range…

Superconductivity · Physics 2007-05-23 Y. L. Liu , T. K. Ng

We investigate the dynamical effects of pairing interaction on superconductivity in BCS-BEC crossover by studying the Holstein model at half-filling where the electron-phonon coupling $g$ controls the crossover. The dynamical mean-field…

Superconductivity · Physics 2019-05-15 Tae-Ho Park , Han-Yong Choi

The lowest adiabatic potential expressed in hyperspherical coordinates is estimated for two boson systems in an external harmonic trap. Corresponding conditions for stability are investigated and the related structures are extracted for…

Other Condensed Matter · Physics 2016-08-31 T. Sogo , O. Sørensen , A. S. Jensen , D. V. Fedorov

We use a slave-boson approach to study the band renormalization and pair susceptibility in the normal state of Iron-based superconductors in presence of strong Coulomb repulsion and Hund's interaction. Our results show orbital selectivity…

Superconductivity · Physics 2025-09-30 Yashar Komijani , Elio Koenig , Piers Coleman

Superconducting electron systems of solids hosting flat bands are studied, with a view to improved understanding of the fundamental physics giving rise to high-temperature superconductivity. We present a modified form of the set of Gor'kov…

Strongly Correlated Electrons · Physics 2017-02-03 V. A. Khodel , J. W. Clark , M. V. Zverev

The two-dimensional Hubbard model is studied for small values of the interaction strength (U of the order of the hopping amplitude t), using a variational ansatz well suited for this regime. The wave function, a refined Gutzwiller ansatz,…

Superconductivity · Physics 2019-07-19 Dionys Baeriswyl

In the [BCS] paper the theory of superconductivity was developed for the BCS model, in which the (instantaneous) interaction is only between fermions of opposite momentum and spin. Such model was analyzed by variational methods, finding…

Strongly Correlated Electrons · Physics 2015-06-25 Vieri Mastropietro

We prove that the steady state of a class of multidimensional reaction-diffusion systems is asymptotically stable at the intersection of unweighted space and exponentially weighted Sobolev spaces, and pay particular attention to a special…

Analysis of PDEs · Mathematics 2022-05-06 Qingxia Li , Xinyao Yang

The dynamical equations of an electromagnetic field coupled with a conducting material are studied. The properties of the interaction are described by a classical field theory with tensorial material laws in space-time geometry. We show…

Superconductivity · Physics 2009-11-11 A Badia-Majos , J F Cariñena , C Lopez