Dynamics of Josephson junctions and single-flux-quantum networks with superconductor–insulator–normal-metal junction shunts

Abstract

Within the framework of the microscopic model of tunneling, we modeled the behavior of the Josephson junction shunted by the superconductor-insulator-normal-metal ͑SIN͒ tunnel junction. The electromagnetic impedance of the SIN junction includes both the frequency-dependent damping and reactance, which affect the circuit dynamics. We calculated the dc I-V curves and transient characteristics and show their differences to the characteristics obtained within the simpler models. The correct operation of the basic single-flux-quantum circuits, i.e., the Josephson transmission line and the toggle flip-flop, based on such SIN-shunted Josephson junctions with small damping at low frequencies, has also been modeled.

Noise-induced effects in nonlinear relaxation of condensed matter systems

“…In this mesoscopic device, macroscopic quantities as voltage and current are directly related to a microscopic order parameter ϕ, representing the phase difference between the wavefunctions of charge carriers in the two superconducting electrodes. In fact, great attention has been paid to JJs as superconducting quantum bits [1][2][3][4], nanoscale superconducting quantum interference devices for detecting weak flux changes [5,6], and threshold noise detectors [7][8][9][10]. Moreover JJs are typical out of equilibrium systems characterised by tilted or switching periodic potentials [11,12], and the effects both of thermal and nonthermal noise sources on the transient dynamics of JJs have recently attracted considerable interest [13][14][15][16][17][18][19][20][21][22][23].…”

Non-Gaussian noise effects in the dynamics of a short overdamped Josephson junction

“…Moreover, JJs present a wide range of applications. In particular, in recent years, the JJs have been used to implement both superconducting quantum bits [5][6][7][8] and nanoscale superconducting quantum interference devices for detecting weak magnetic flux changes [9]. Josephson junctions, in fact, represent good candidates to realize solid state superconducting quantum bits (qubits) for quantum information processing.…”

Josephson flux-flow oscillator: The microscopic tunneling approach

“…Uses of the MTT include modeling SQUIDs [26,27], Josephson arrays [28], and RSFQ logic gates and circuits [29][30][31][32][33][34]. While in the early days the attention to the phase-dependent dissipative current was motivated mainly by the cos ϕ problem, it has seen a revival very recently [35][36][37][38][39][40][41][42]-this time, from the practical * d.r.gulevich@metalab.ifmo.ru side: the phase-dependent dissipation has found application in the proposal of superconducting memristor [37,38], has been considered to be a source of relaxation in superconducting qubits [39][40][41][42], and has even shown to be a powerful tool to suppress dissipation in fluxonium qubit [36].…”