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We study theoretically the large variations of the supercurrent through a normal dot that are induced by a small quasiparticle injection current from normal leads connected to the dot. We find that the supercurrent decomposes into a subgap…

Superconductivity · Physics 2022-12-07 Sarath Sankar , Julia S. Meyer , Manuel Houzet

We measure the non-dissipative supercurrent in a single InAs self-assembled quantum dot (QD) coupled to superconducting leads. The QD occupation is both tuned by a back-gate electrode and lateral side-gate. The geometry of the side-gate…

Mesoscale and Nanoscale Physics · Physics 2010-09-30 Y. Kanai , R. S. Deacon , A. Oiwa , K. Yoshida , K. Shibata , K. Hirakawa , S. Tarucha

We study the electric and thermoelectric transport properties of correlated quantum dots coupled to two ferromagnetic leads and one superconducting electrode. Transport through such hybrid devices depends on the interplay of…

Mesoscale and Nanoscale Physics · Physics 2015-06-19 Krzysztof P. Wojcik , Ireneusz Weymann

In this paper, we investigate the electronic transport properties of a quantum dot (QD) connected to two ferromagnetic leads and one superconductor lead in the Kondo regime by means of the finite-$U$ slave boson mean field approach and…

Mesoscale and Nanoscale Physics · Physics 2020-01-08 C. Lee , Bing Dong , X. L. Lei

We realize a hybrid superconductor-semiconductor transmon device in which the Josephson effect is controlled by a gate-defined quantum dot in an InAs/Al nanowire. Microwave spectroscopy of the transmon's transition spectrum allows us to…

Even in the absence of Coulomb interactions phase fluctuations induced by quantum size effects become increasingly important in superconducting nano-structures as the mean level spacing becomes comparable with the bulk superconducting gap.…

Superconductivity · Physics 2014-03-05 Pedro Ribeiro , Antonio M. García-García

In this work, we manipulate the phase shift of a Josephson junction using a parallel double quantum dot (QD). By employing a superconducting quantum interference device, we determine how orbital hybridization and detuning affect the…

The Josephson effect describes supercurrent flowing through a junction connecting two superconducting leads by a thin barrier [1]. This current is driven by a superconducting phase difference $\phi$ between the leads. In the presence of…

Mesoscale and Nanoscale Physics · Physics 2017-07-28 D. B. Szombati , S. Nadj-Perge , D. Car , S. R. Plissard , E. P. A. M. Bakkers , L. P. Kouwenhoven

The superconducting proximity effect is probed experimentally in Josephson junctions fabricated with InAs nanowires contacted by Nb leads. Contact transparencies $t \sim 0.7$ are observed. The electronic phase coherence length at low…

Mesoscale and Nanoscale Physics · Physics 2017-03-08 Kaveh Gharavi , Gregory W. Holloway , Ray R. LaPierre , Jonathan Baugh

We study a strongly interacting quantum dot connected to two superconducting leads using a slave-spin representation of the dot. At the mean-field level, the problem maps to a resonant level model with superconducting leads, coupled to an…

Mesoscale and Nanoscale Physics · Physics 2026-05-14 Andriani Keliri , Marco Schirò

We perform supercurrent and tunneling spectroscopy measurements on gate-tunable InAs/Al Josephson junctions (JJs) in an in-plane magnetic field, and report on phase shifts in the current-phase relation measured with respect to an absolute…

Josephson junction arrays are ideal model systems where a variety of phenomena, phase transitions, frustration effects, vortex dynamics, chaos, to mention a few of them, can be studied in a controlled way. In this review we focus on the…

Condensed Matter · Physics 2009-10-31 Rosario Fazio , Herre van der Zant

We analyze the ground state properties of an array of quantum dots connected in series between superconducting electrodes. This system is represented by a finite Hubbard chain coupled at both ends to BCS superconductors. The ground state is…

Superconductivity · Physics 2009-11-13 F. S. Bergeret , A. Levy Yeyati , A. Martin-Rodero

We study Josephson junctions based on second-order topological superconductors (SOTSs) which can be realized in quantum spin Hall insulators with large inverted gap in proximity to unconventional superconductors. We find that tuning the…

Superconductivity · Physics 2020-01-22 Song-Bo Zhang , Björn Trauzettel

We investigate the quantum phase transition in a one-dimensional chain of ultra-small superconducting grains, considering both the self- and junction capacitances. At zero temperature, the system is transformed into a two-dimensional system…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 Mahn-Soo Choi , J. Yi , M. Y. Choi , J. Choi , S. -I. Lee

We show that a system of Josephson junctions coupled via low-resistance tunneling contacts to graphene substrate(s) may effectively operate as a current switching device. The effect is based on the dissipation-driven…

Superconductivity · Physics 2009-11-13 Roman M. Lutchyn , Victor Galitski , Gil Refael , S. Das Sarma

We study the interplay between the Kondo and Andreev-Josephson effects in a quantum dot coupled to one normal and two superconducting (SC) leads. In the large gap limit, the low-energy states of this system can be described exactly by a…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 Akira Oguri , Yoichi Tanaka

We study quantum phase-slip (QPS) processes in a superconducting ring containing N Josephson junctions and threaded by an external static magnetic flux. In a such system, a QPS consists of a quantum tunneling event connecting two distinct…

Superconductivity · Physics 2015-03-19 G. Rastelli , I. M. Pop , F. W. J. Hekking

Josephson junctions translate quantum phase coherence into an electrical response and underpin superconducting sensors and quantum circuits. In conventional junctions, the barrier acts primarily as a passive weak link, however, when the…

A growing body of work suggests that planar Josephson junctions fabricated using superconducting hybrid materials provide a highly controllable route toward one-dimensional topological superconductivity. Among the experimental controls are…