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Related papers: Ward Identities for Cooper Pairs

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Two thermodynamic relations are proposed for the exact measurement of the center-of-mass (COM) momentum of the Cooper pairs in helical superconductors. The first relation concerns the constraint on the change in the COM momentum in response…

Superconductivity · Physics 2024-10-11 Koki Shinada , Robert Peters

We verify the QED Ward identity for the two- and three -point functions at non-equilibrium in the HTL limit. We use the Keldysh formalism of real time finite temperature field theory. We obtain an identity of the same form as the Ward…

High Energy Physics - Theory · Physics 2009-10-31 M. E. Carrington , Hou Defu , Markus H. Thoma

The Cooper pair is generally analyzed in momentum space, but its real-space structure also follows directly from the BCS theory. It is shown here that this leads to a spherically symmetrical quasi-atomic wavefunction, with an identical…

Superconductivity · Physics 2007-05-23 Alan M. Kadin

We discuss the normal state of a fermionic system in an idealized PSEUDOGAP REGIME, $k_B T_c < k_B T << |\Delta| << E_F$. Stable Cooper pairs induce a pseudogap of width $|\Delta|$ in the fermion energy spectrum. Near two dimensions, we…

Condensed Matter · Physics 2015-06-25 O. Tchernyshyov , Y. J. Uemura

We derive, based on the Wakimoto realization, the integral formulas for the WZNW correlation functions. The role of the ``screening currents Ward identity'' is demonstrated with explicit examples. We also give a more simple proof of a…

High Energy Physics - Theory · Physics 2008-11-26 Hidetoshi Awata

We measure an aluminum superconducting double quantum dot and find that its electrical impedance, specifically its quantum capacitance, depends on whether or not it contains a single broken Cooper pair. In this way we are able to observe,…

Mesoscale and Nanoscale Physics · Physics 2017-07-17 N. J. Lambert , M. Edwards , A. A. Esmail , F. A. Pollock , S. D. Barrett , B. W. Lovett , A. J. Ferguson

The binding energy of Cooper pairs has been calculated for the case of d-wave symmetry of the superconducting gap in layered cuprate superconductors. We assume that Cooper pairs are formed by the short range potential and then derive the…

Superconductivity · Physics 2007-05-23 I. E. Lyubin , M. V. Eremin

When quantum fluctuations in the phase of the superconducting order parameter destroy the off-diagonal long range order, duality arguments predict the formation of a Cooper pair crystal. This effect is thought to be responsible for the…

Superconductivity · Physics 2009-11-11 T. Pereg-Barnea , M. Franz

It is demonstrated that non local Cooper pairs can propagate in ferromagnetic electrodes having an opposite spin orientation. In the presence of such crossed correlations, the superconducting gap is found to depend explicitly on the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 R. Mélin

The pair density wave (PDW) exemplifies intertwined orders in strongly correlated systems. A recent discovery of superconductivity in a quarter-metal state offers the first experimental system where a pure PDW without uniform…

Superconductivity · Physics 2025-06-11 Omri Lesser , Chunli Huang , James P. Sethna , Eun-Ah Kim

A Cooper-pair or electron-hole splitter is a device capable of spatially separating entangled fermionic quasiparticles into mesoscopic solid-state systems such as quantum dots or quantum wires. We theoretically study such a splitter based…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 Koji Sato , Yaroslav Tserkovnyak

We derive spectral representations for the different components of the 4-point function at finite temperature in the real time formalism in terms of five real spectral densities. We explicitly calculate all these functions in QED in the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Hou Defu , M. E. Carrington , R. Kobes , U. Heinz

We propose utilizing the Cooper pair to induce magnetic frustration in systems of two-dimensional (2D) magnetic adatom lattices on s-wave superconducting surfaces. The competition between singlet electron correlations and the RKKY coupling…

Strongly Correlated Electrons · Physics 2018-05-15 Michael Schecter , Olav F. Syljuåsen , Jens Paaske

The internal chirality of Cooper pairs is shown to modify strongly the response of a superconductor to the local heating by a laser beam. The suppression of the chiral order parameter inside the hot spot appears to induce the supercurrents…

Superconductivity · Physics 2017-12-06 V. L. Vadimov , A. S. Mel'nikov

We derive the spectral representations of QED 3-point functions and then explicitly calculate the 3-point spectral densities in hard thermal loop approximation within the real time formalism. The Ward identities obeyed by the retarded and…

High Energy Physics - Theory · Physics 2009-10-09 Hou Defu , U. Heinz

There has been strong interest recently in the so-called Cooper pair density wave, subsequent to the proposition that such a state occurs in the hole-doped cuprate superconductors. As of now there is no convincing demonstration of such a…

Strongly Correlated Electrons · Physics 2024-06-25 Sumit Mazumdar , R. Torsten Clay

Paramagnetic effects are shown to result in the appearance of a triplet component of order parameter in a vortex phase of a d-wave superconductor in the absence of impurities. This component, which breaks both parity and time-reversal…

Superconductivity · Physics 2009-11-11 A. G. Lebed

Using gauge transformations on electron bond operators, we derive exact duality relations between various order parameters for correlated electron systems. Applying these transformations, we find two duality relations in the generalized…

Strongly Correlated Electrons · Physics 2007-05-23 Tsutomu Momoi , Toshiya Hikihara

Cooper quartets represent exotic fermion aggregates describing correlated matter at the basis of charge-$4e$ superconductivity and offer a platform for studying four-body interactions, of interest for topologically protected quantum…

Mesoscale and Nanoscale Physics · Physics 2024-10-08 Luca Chirolli , Alessandro Braggio , Francesco Giazotto

Bloch wave functions of electrons have properties called quantum geometry, which has recently attracted much attention as the origin of intriguing physical phenomena. In this paper, we introduce the notion of the quantum-geometric pair…

Superconductivity · Physics 2024-09-12 Akito Daido , Taisei Kitamura , Youichi Yanase