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Related papers: On the Puzzle of Odd-Frequency Superconductivity

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Topological superconductors give rise to unconventional superconductivity, which is mainly characterized by the symmetry of the superconducting pairing amplitude. However, since the symmetry of the superconducting pairing amplitude is not…

Superconductivity · Physics 2018-05-09 C. Fleckenstein , N. Traverso Ziani , B. Trauzettel

We consider excitation of Higgs modes via the modulation of the BCS coupling within the Migdal-Eliashberg-Keldysh theory of time-dependent superconductivity. Despite the presence of phonons, which break integrability, we observe Higgs…

Superconductivity · Physics 2025-01-15 Andrey Grankin , Victor Galitski , Vadim Oganesyan

Odd-frequency superconductivity describes a class of superconducting states where the superconducting gap is an odd function in relative time and Matsubara frequency. We present a group theoretical analysis based on the linearized gap…

Superconductivity · Physics 2018-01-17 R. Matthias Geilhufe , Alexander V. Balatsky

Using a simple theoretical model, we demonstrate the emergence of odd-frequency pair amplitudes in conventional Josephson junctions both in the absence of a voltage (DC effect) and in the presence of a finite voltage (AC effect). In both…

Superconductivity · Physics 2018-04-20 Alexander V. Balatsky , Sergey S. Pershoguba , Christopher Triola

We discuss odd-frequency Cooper pairs appearing in two-band superconductors by solving the Gor'kov equation analytically. We introduce the equal-time $s$-wave pair potentials as realized in MgB$_2$ and iron pnictides. Although the order…

Superconductivity · Physics 2020-07-21 Yasuhiro Asano , Akihiro Sasaki

The spin transport inside an odd-frequency spin-triplet superconductor differs from that of a conventional superconductor due to its distinct symmetry properties. We study spin transport inside an emergent odd-frequency superconductor by…

Superconductivity · Physics 2021-11-10 Lina G. Johnsen , Jacob Linder

We suggest a novel nonlinear $\sigma$-model for the description of disordered superconductors. The main distinction from existing models lies in the fact that the saddle point equation is solved non-perturbatively in the superconducting…

Superconductivity · Physics 2009-10-31 I. V. Yurkevich , Igor V. Lerner

We first show the realization of exceptional points in a non-Hermitian superconducting system based on a conventional superconductor and then demonstrate that, surprisingly, the system hosts odd-frequency pairing, solely generated by the…

Superconductivity · Physics 2022-03-08 Jorge Cayao , Annica M. Black-Schaffer

From the outset of superconductivity research it was assumed that no electrostatic fields could exist inside superconductors, and this assumption was incorporated into conventional London electrodynamics. Yet the London brothers themselves…

Superconductivity · Physics 2012-07-06 J. E. Hirsch

Even- and odd-frequency superconductivity coexist due to broken time-reversal symmetry under magnetic field. In order to describe this mixing, we extend the linearized Eliashberg equation for the spin and charge fluctuation mechanism in…

Superconductivity · Physics 2018-01-17 Kiyu Fukui , Yusuke Kato

We discuss the instability of uniform superconducting states that contain the pairing correlations belonging to the odd-frequency symmetry class. The instability originates from the paramagnetic response of odd-frequency Cooper pairs and is…

Superconductivity · Physics 2024-10-17 Takumi Sato , Shingo Kobayashi , Yasuhiro Asano

Conventional superconductors are strong diamagnets that through the Meissner effect expel magnetic fields. It would therefore be surprising if a superconducting ground state would support spontaneous magnetics fields. Such time-reversal…

Superconductivity · Physics 2015-09-02 Mikael Håkansson , Tomas Löfwander , Mikael Fogelström

It is now well established that at a superconductor/ferromagnet (S/F) interface an unconventional superconducting state arises in which the pairing state is odd-frequency. The hallmark signature of this superconducting state is generally…

Superconductivity · Physics 2015-10-28 J. Linder , J. W. A. Robinson

We investigate the possible superconducting instabilities of strongly correlated electron materials using a generalization of linear response theory to external pairing fields depending on frequency. We compute a pairing susceptibility…

Superconductivity · Physics 2024-09-18 Olivier Gingras , Antoine Georges , Olivier Parcollet

The theory of superconductivity developed by Bardeen, Cooper and Schrieffer (BCS) explains the stabilization of electron pairs into a spin-singlet, even frequency, state by the formation of an energy gap within which the density of states…

A new class of singlet superconductors with a gap function $\Delta(\bk, \omega_n)$ which is {\it odd} in both momentum and Matsubara frequency is considered. Some of the physical properties of this superconductivity are discussed and it is…

Condensed Matter · Physics 2007-05-23 Alexander Balatsky , Elihu Abrahams

It has been commonly accepted that magnetic field suppresses superconductivity by inducing the ordered motion of Cooper pairs. We demonstrate that magnetic field can instead provide a generation of superconducting correlations by inducing…

Superconductivity · Physics 2020-10-07 M. A. Silaev , I. V. Bobkova , A. M. Bobkov

We present a necessary condition for odd-frequency (odd-f) superconductivity (SC) to occur in a large class of materials described by Eliashberg theory. We use this condition to prove a no-go theorem ruling out the occurrence of odd-f SC in…

Superconductivity · Physics 2022-07-06 Edwin Langmann , Christian Hainzl , Robert Seiringer , Alexander V. Balatsky

The superconducting order parameter of strontium ruthenate is the center of a lasting puzzle calling for theoretical studies that include the seldom-considered effects of spin-orbit coupling and the frequency-dependence of the order…

Superconductivity · Physics 2022-09-01 Olivier Gingras , Nikita Allaglo , Reza Nourafkan , Michel Côté , André-Marie S. Tremblay

We consider the model of superconducting pairing with the energy gap function which is odd over $k-k_{F}$.\ In this case superconductivity is possible even in the presence of an arbitrarily large point-like repulsion between electrons,\…

Condensed Matter · Physics 2007-05-23 E. Z. Kuchinskii , M. V. Sadovskii , M. A. Erkabaev