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We study the Josephson current in two types of lateral junctions with spin-orbit coupling and an exchange field. The first system (type 1 junction) consists of superconductors with heavy metal interlayers linked by a ferromagnetic bridge,…

Superconductivity · Physics 2020-01-01 B. Bujnowski , R. Biele , F. S. Bergeret

We investigate the supercurrent through a quantum dot for the whole range of couplings using the numerical renormalization group method. We find that the Josephson current switches abruptly from a $\pi$- to a 0-phase as the coupling…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Mahn-Soo Choi , Minchul Lee , Kicheon Kang , W. Belzig

The fluxon dynamics in a long Josephson junction with a ferromagnetic insulating layer is investigated. It is found that the Josephson phase obeys a double sine-Gordon equation involving a bound pi fluxon solution, and the internal…

Superconductivity · Physics 2009-11-13 Munehiro Nishida , Kyoko Murata , Toshiyuki Fujii , Noriyuki Hatakenaka

With the help of the numerical renormalization group method, we theoretically investigate the Josephson phase transition in a parallel junction with one quantum dot embedded in each arm. It is found that in the cases of uniform dot levels…

Mesoscale and Nanoscale Physics · Physics 2018-08-08 Guang-Yu Yi , Xiao-Qi Wang , Cui Jiang , Wei-Jiang Gong

We study the T=0 normal to superconducting transition of Josephson arrays with {\it on-site} dissipation. A perturbative renormalization group solution is given. Like the previously studied case of {\it bond} dissipation (BD), this is a…

Statistical Mechanics · Physics 2009-11-11 Sumanta Tewari , John Toner

Josephson junction arrays can be used as quantum channels to transfer quantum information between distant sites. In this work we discuss simple protocols to realize state transfer with high fidelity. The channels do not require complicate…

Quantum Physics · Physics 2009-11-10 Alessandro Romito , Rosario Fazio , C. Bruder

Atomtronics has the potential for engineering new types of functional devices, such as Josephson junctions (JJs). Previous studies have mainly focused on JJs whose ground states have 0 or $\pi $ superconducting phase difference across the…

Quantum Gases · Physics 2016-10-19 Lei Jiang , Yong Xu , Chuanwei Zhang

We apply a Gutzwiller-like variational technique to study Josephson conduction across a quantum dot with an odd number of electrons connected to two superconducting leads. We show that, for small values of the superconducting gap, Kondo…

Strongly Correlated Electrons · Physics 2007-05-23 G. Campagnano , D. Giuliano , A. Tagliacozzo

We propose novel model system for the studies of superconductor-insulator transitions, which is a regular lattice, whose each link consists of Josephson-junction chain of $N \gg 1$ junctions in sequence. The theory of such an array is…

Superconductivity · Physics 2022-06-01 I. V. Protopopov , M. V. Feigel'man

We consider dissipative quantum phase transitions in Josephson junction arrays and show that the disordered phase in this extended system can be viewed as an unusual floating phase in which the states of local $(0+1)$-dimensional elements…

Statistical Mechanics · Physics 2007-05-23 Sumanta Tewari , John Toner , Sudip Chakravarty

A transition between the strong (coherent) and weak (incoherent) coupling limits of resonant interaction between quantum well (QW) excitons and bulk photons is analyzed and quantified as a function of the incoherent damping rate caused by…

Mesoscale and Nanoscale Physics · Physics 2008-03-04 C. Creatore , A. L. Ivanov

A system of two parallel Josephson junction arrays coupled by interlayer capacitances is considered in the situation where one layer is in the vortex-dominated and the other in the charge-dominated regime. This system shows a symmetry…

Condensed Matter · Physics 2009-10-28 Yaroslav M. Blanter , Gerd Schoen

The direct effect of an axion field on Josephson junctions is analyzed through the consequences on the effective potential barrier that prevents the junction from switching from the superconducting to the finite-voltage state. We describe a…

High Energy Physics - Phenomenology · Physics 2023-09-06 Roberto Grimaudo , Davide Valenti , Bernardo Spagnolo , Antonio Troisi , Giovanni Filatrella , Claudio Guarcello

We analyze the coherent dynamics of a fluxonium device (Manucharyan et al 2009 Science 326 113) formed by a superconducting ring of Josephson junctions in which strong quantum phase fluctuations are localized exclusively on a single weak…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 G. Rastelli , M. Vanevic , W. Belzig

A quantum mechanical analysis of the Josephson phase escape in the presence of both dc and ac bias currents is presented. We find that the potential barrier for the escape of the phase is effectively suppressed as the resonant condition…

Superconductivity · Physics 2009-11-10 M. V. Fistul , A. Wallraff , A. V. Ustinov

We consider the current-phase relation (CPR) in the Josephson junctions with complex insulator-superconductor-ferromagnetic interlayers in the vicinity of 0-$\pi$ transition. We find a strong impact of the second harmonic on CPR of the…

We derive the radiation power from a single Josephson junction (JJ) and from layered superconductors in the flux-flow regime. For the JJ case we formulate the boundary conditions for the electric and magnetic fields at the edges of the…

Superconductivity · Physics 2007-05-23 L. N. Bulaevskii , A. E. Koshelev

We study a 1-D array of Josephson coupled superconducting grains with kinetic inductance which dominates over the Josephson inductance. In this limit the dynamics of excess Cooper pairs in the array is described in terms of charge solitons,…

Condensed Matter · Physics 2009-10-28 Ziv Hermon , Eshel Ben-Jacob , Gerd Schön

Using the path integral approach, we provide an explicit derivation of the equation for the phase boundary for quantum Josephson junction arrays with offset charges and non-diagonal capacitance matrix. For the model with nearest neighbor…

Superconductivity · Physics 2009-10-31 G. Grignani , A. Mattoni , P. Sodano , A. Trombettoni

We consider a simple model for an SNS Josephson junction in which the "normal metal" is a section of a filling-factor $\nu=2$ integer quantum-Hall edge. We provide analytic expressions for the current/phase relations to all orders in the…

Superconductivity · Physics 2015-03-19 Michael Stone , Yiruo Lin