Josephson-junction arrays are ideal model systems to study a variety of phenomena such as phase transitions, frustration effects, vortex dynamics and chaos. In this review, we focus on the quantum dynamical properties of lowcapacitance Josephson-junction arrays. The two characteristic energy scales in these systems are the Josephson energy, associated with the tunneling of Cooper pairs between ...

Motivated by recent pump-probe experiments indicating enhanced coherent c-axis transport in underdoped YBCO, we study Josephson junctions periodically driven by optical pulses. We propose a mechanism for this observation by demonstrating that a parametrically driven Josephson junction shows an enhanced imaginary part of the low-frequency conductivity when the driving frequency is above the plas...

The Josephson effect is a fundamental quantum phenomenon where a dissipationless supercurrent is introduced in a weak link between two superconducting electrodes by Andreev reflections. The physical details and topology of the junction drastically modify the properties of the supercurrent and a strong enhancement of the critical supercurrent is expected to occur when the topology of the junctio...

We investigate the Josephson effects in the junction formed by the indirect coupling between DIII-class topological and s-wave superconductors via an embedded quantum dot. Due to the presence of two kinds of superconductors, three dot-superconductor coupling manners are considered, respectively. As a result, the Josephson current is found to oscillate in period 2π. More importantly, the presenc...

Anyons are particles with intermediate quantum statistics whose wavefunction acquires a phase $e^{i\theta}$ by particle exchange. Inspired proposals of simulating anyons using ultracold atoms trapped in optical lattices, we study two-site anyonic Josephson junction, i.e. confined one-dimensional double-well potential. We show, analytically and numerically, that many properties junctions, such a...

Abstract Cuprate superconductor Bi 2 Sr CaCu O 8+ δ (BSCCO) has been a promising candidate of coherent, continuous, and compact THz light source owing to its intrinsic Josephson junction (IJJ) inside the crystal structure. In this paper, we utilized BSCCO cross-whisker (CW) junctions produce emitter device using whisker crystals which can be easily obtained compared with single crystals. As res...

This thesis presents a study of resonance dynamics in circuits of superconducting Josephson junctions. The Josephson junction is an intrinsically nonlinear device which, under certain conditions, can exhibit harmonic oscillations. This research begins with the dynamics of Josephson junctions connected in parallel with either periodic (ring geometry) or open-ended (row geometry) boundary conditi...

We present a theory for the nonequilibrium current in a mesoscopic Josephson junction which is coupled to a normal electron reservoir, and apply it to a chaotic junction. Large sample-to-sample fluctuations of the critical current Ic are found, with rms Ic.ANeD/\ , when the voltage difference eV between the electron reservoir and the junction exceeds the superconducting gap D and the number of ...

In this paper we consider the Rapid Single-Flux Quantum (RSFQ) circuits with reduced Josephson current density and especially deal with one of the basic building blocks of these electronics the DC to SFQ converter. For future promising RSFQ applications the critical current of the Josephson junctions should be reduced (by reduction of Josephson current density) to several μA, resulting into val...