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Related papers: Multiband model for tunneling in MgB2 junctions

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Mesoscopic multi-terminal Josephson junctions are novel devices that provide weak coupling between several bulk superconductors through a common normal layer. Because of the nonlocal coupling of the superconducting banks, a current flow…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 M. H. S. Amin , A. N. Omelyanchouk , A. Blais , A. Maassen van den Brink , G. Rose , T. Duty , A. M. Zagoskin

Scanning tunneling spectroscopy was performed on single crystals of superconducting 2H-NbSe2, at 300 mK and in a magnetic field, up to 5 T, applied parallel to the ab-plane. This novel field geometry allows the quasiparticle…

Superconductivity · Physics 2011-11-01 I. Fridman , C. Kloc , J. Y. T. Wei

Establishment of phase-coherence and a non-dissipative (super)current between two weakly coupled superconductors, known as the Josephson effect, plays a foundational role in basic physics and applications to metrology, precision sensing,…

Bosonic Josephson junctions can be realized by confining ultracold gases of bosons in multi-well traps, and studied theoretically with the $M$-site Bose-Hubbard model. We show that canonical equilibrium states of the $M$-site Bose-Hubbard…

Atomic Physics · Physics 2009-06-02 Alex D. Gottlieb , Thorsten Schumm

Homogeneous current states in thin films and Josephson current in superconducting microbridges are studied within the frame of a two-band Ginzburg-Landau theory. By solving the coupled system of equations for two order parameters the…

Superconductivity · Physics 2009-11-11 Y. S. Yerin , A. N. Omelyanchouk

We study theoretically the Josephson effect between two time-reversal two-band superconductors, where we assume the equal-time spin-singlet $s$-wave pair potential in each conduction band. %as well as the band asymmetry and the band…

Superconductivity · Physics 2020-05-13 Akihiro Sasaki , Satoshi Ikegaya , Tetsuro Habe , Alexander A. Golubov , Yasuhiro Asano

We report first-principles calculations of the k- and T-dependent superconducting gap Delta(k,T) in MgB2 and its manifestation in various measured quantities. Because the Fermi surface has disconnected sheets with different electron-phonon…

Superconductivity · Physics 2007-05-23 Hyoung Joon Choi , David Roundy , Hong Sun , Marvin L. Cohen , Steven G. Louie

It has recently been observed that MgB_2 is a superconductor with a high transition temperature. Here we propose a model of anisotropic s-wave superconductivity which consistently describes the observed properties of this compound,…

Superconductivity · Physics 2009-11-07 Stephan Haas , Kazumi Maki

In an in-situ prepared three-terminal Josephson junction based on the topological insulator Bi$_4$Te$_3$ and the superconductor Nb the transport properties are studied. The differential resistance maps as a function of two bias currents…

Using the tight-binding method for the $\pi$-bands in MgB$_2$, the Hubbard on-site Coulomb interaction on two inequivalent boron $p_z$-orbitals is transformed into expressions in terms of $\pi$-band operators. For scattering processes…

Superconductivity · Physics 2009-11-07 Kunihiko Yamaji

We report tunneling measurements of the electron-phonon (e-ph) interaction in superconducting MgB$_2$ using the MgB$_2$-I-Nb junctions, where I stands for insulator. The phonon structure in tunneling density of states in MgB$_2$ clearly…

Superconductivity · Physics 2007-05-23 A. I. D'yachenko , V. Yu. Tarenkov , A. V. Abal'oshev , S. J. Lewandowski

We present a consistent theory of superconductive tunneling in single-mode junctions within a scattering formulation of Bogoliubov-de Gennes quantum mechanics. Both dc Josephson effect and dc quasiparticle transport in voltage biased…

Superconductivity · Physics 2009-10-28 V. S. Shumeiko , E. N. Bratus' , G. Wendin

The quantised Josephson junction equation that underpins the behaviour of charge qubits and other tunnel devices is usually derived through cannonical quantisation of the classical macroscopic Josephson relations. However, this approach may…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 D. A. Rodrigues , T. P. Spiller , J. F. Annett , B. L. Györffy

The concept of thermophase refers to the appearance of a phase gradient inside a superconductor originating from the presence of an applied temperature bias across it. The resulting supercurrent flow may, in suitable conditions, fully…

Mesoscale and Nanoscale Physics · Physics 2015-02-11 F. Giazotto , T. T. Heikkilä , F. S. Bergeret

We study the nonequilibrium dynamics of multiband BCS superconductors subjected to ultrashort pump pulses. Using density-matrix theory, the time evolution of the Bogoliubov quasiparticle densities and the superconducting order parameters…

Superconductivity · Physics 2013-01-10 Alireza Akbari , Andreas P. Schnyder , Dirk Manske , Ilya Eremin

We introduce a new approach to the Josephson effect in SIS tunnel junctions. The Josephson coupling energy is calculated from the overlap of real space Cooper pair wavefunctions in two superconductors through an insulating barrier. It is…

Superconductivity · Physics 2007-05-23 Yong-Jihn Kim

We present an analytical description of the tunneling dynamics between two coupled Bose-Einstein condensates in the Josephson regime. The model relies on the classical analogy with a rigid pendulum and focuses on two dynamical modes of this…

Quantum Physics · Physics 2018-12-31 Marine Pigneur , Jörg Schmiedmayer

It is important to know the decoherence mechanism of a qubit based on Josephson junctions. At low temperatures, as quasiparticle concentration becomes exponentially small, one needs to consider energy transfer from tunneling electrons to…

Superconductivity · Physics 2014-08-15 L. N. Bulaevskii , Shi-Zeng Lin

We analyze the qualitative features in the transition spectra of a model superconductor with multiple energy gaps, using a simple extension of the Mattis-Bardeen expression for probes with case I and case II coherence factors. At…

Superconductivity · Physics 2009-11-07 Sergey V. Barabash , David Stroud

A Josephson tunnel junction which is RF-driven near a dynamical bifurcation point can amplify quantum signals. The bifurcation point will exist robustly only if the electrodynamic environment of the junction meets certain criteria. In this…

Superconductivity · Physics 2009-11-11 V. E. Manucharyan , E. Boaknin , M. Metcalfe , R. Vijay , I. Siddiqi , M. H. Devoret