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Related papers: Coherent dynamics in long fluxonium qubits

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We propose a qubit-qubit coupling scheme for superconducting flux quantum bits (qubits), where a quantized Josephson junction resonator and microwave irradiation are utilized. The junction is used as a tunable inductance controlled by…

Superconductivity · Physics 2009-11-13 H. Nakano , K. Kakuyanagi , M. Ueda , K. Semba

Multiterminal Josephson junctions are a promising platform to host synthetic topological phases of matter and Floquet states. However, the energy scales governing topological protection in these devices are on the order of the spacing…

Circuit quantum electrodynamics, where photons are coherently coupled to artificial atoms built with superconducting circuits, has enabled the investigation and control of macroscopic quantum-mechanical phenomena in superconductors.…

In this work, we study a Josephson junction with parallel-connected quantum dots (QDs) threaded by a magnetic flux in the central region. We discretize the superconducting (SC) electrode into three discrete energy levels and modify the…

Mesoscale and Nanoscale Physics · Physics 2026-04-30 Yiyan Wang , Cong Li , Bing Dong

We report on the observation of the Josephson effect between two strongly interacting fermionic superfluids coupled through a thin tunneling barrier. We prove that the relative population and phase are canonically conjugate dynamical…

Single flux quantum (SFQ) circuitry is a promising candidate for a scalable and integratable cryogenic quantum control system. However, the operation of SFQ circuits introduces non-equilibrium quasiparticles (QPs), which are a significant…

In circuit quantum electrodynamical systems, the quasiparticle-related losses in Josephson junctions are suppressed due to the gap in the superconducting density of states which is much higher than the typical energy of a microwave photon.…

Quantum Physics · Physics 2025-10-08 Vasilii Vadimov , Yoshiki Sunada , Mikko Möttönen

We investigate the phase dynamics of a long Josephson junction (LJJ) with two-gap superconductors. In this junction, two channels for tunneling between the adjacent superconductor (S) layers as well as one interband channel within each S…

Superconductivity · Physics 2015-06-04 Ju H. Kim , Bal-Ram Ghimire , Hao-Yu Tsai

The possibility of making a flux qubit on nonsuperconducting mesoscopic ballistic quasi 1D ring is discussed. We showed that such ring can be effectively reduced to a two-state system with two external control parameters. The two states…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 E. Zipper , M. Kurpas , M. Szelag , J. Dajka , M. Szopa

We report a superconducting artificial atom with an observed quantum coherence time of T2*=95us and energy relaxation time T1=70us. The system consists of a single Josephson junction transmon qubit embedded in an otherwise empty copper…

We study mesoscopic fluctuations and weak localization correction to the supercurrent in Josephson junctions with coherent diffusive electron dynamics in the normal part. Two kinds of junctions are considered: a chaotic dot coupled to…

Mesoscale and Nanoscale Physics · Physics 2008-03-10 M. Houzet , M. A. Skvortsov

We study the thermodynamic properties of a superconductor/normal metal/superconductor Josephson junction {in the short limit}. Owing to the proximity effect, such a junction constitutes a thermodynamic system where {phase difference},…

Superconductivity · Physics 2019-10-16 Francesco Vischi , Matteo Carrega , Alessandro Braggio , Pauli Virtanen , Francesco Giazotto

In superconducting qubits, the interaction of the qubit degree of freedom with quasiparticles defines a fundamental limitation for the qubit coherence. We develop a theory of the pure dephasing rate \Gamma_{\phi} caused by quasiparticles…

Mesoscale and Nanoscale Physics · Physics 2012-11-22 G. Catelani , Simon E. Nigg , S. M. Girvin , R. J. Schoelkopf , L. I. Glazman

This paper applies recent results on the robust stability of nonlinear quantum systems to the case of a Josephson junction in a resonant cavity. The Josephson junction is characterized by a Hamiltonian operator which contains a…

Quantum Physics · Physics 2016-11-15 Ian R. Petersen

Hybridizing superconductivity with the quantum Hall (QH) effects has major potential for designing novel circuits capable of inducing and manipulating non-Abelian states for topological quantum computation. However, despite recent…

Quantum fluctuations of the phases of the order parameter in 2D arrays of mesoscopic Josephson junctions and their effect on the destruction of superconductivity in the system are investigated by means of a quantum-cosine model that is free…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 A. I. Belousov , Yu. E. Lozovik

In superconducting circuits interrupted by Josephson junctions, the dependence of the energy spectrum on offset charges on different islands is $2e$ periodic through the Aharonov-Casher effect and resembles a crystal band structure that…

Mesoscale and Nanoscale Physics · Physics 2021-07-16 Luca Chirolli , Joel E. Moore

We investigate the superconducting lifetime of long current-biased Josephson junctions, in the presence of Gaussian and non-Gaussian noise sources. In particular, we analyze the dynamics of a Josephson junction as a function of the noise…

Superconductivity · Physics 2015-06-22 Davide Valenti , Claudio Guarcello , Bernardo Spagnolo

We consider a superconducting half-wavelength resonator that is grounded at its both ends and contains a single Josephson junction. Previously this circuit was considered as a unimon qubit in the single-mode approximation where…

We report on ultrastrong coupling between a superconducting flux qubit and a resonant mode of a system comprised of two superconducting coplanar stripline resonators coupled galvanically to the qubit. With a coupling strength as high as 17%…