Related papers: Critical behavior of dynamic vortex Mott transitio…
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…
We investigate mesoscopic Josephson junction arrays created by patterning superconducting disks on monolayer graphene, concentrating on the high-$T/T_c$ regime of these devices and the phenomena which contribute to the superconducting glass…
Quantum phase transitions typically result in a broadened critical or crossover region at nonzero temperature. Josephson arrays are a model of this phenomenon, exhibiting a superconductor-insulator transition at a critical wave impedance,…
We have studied the rationally frustrated Josephson-junction array model in the square lattice through Monte Carlo simulations of $(2+1)$D XY-model. For frustration $f=1/4$, the model at zero temperature shows a continuous…
We measured and compared the electric field vs current density characteristics in the vortex state of two amorphous Nb0.7Ge0.3 microbridges, with and without a line of submicron holes patterned along the sample axis. The power dissipation…
The behavior of a disordered amorphous thin film of superconducting Indium Oxide has been studied as a function of temperature and magnetic field applied perpendicular to its plane. A superconductor-insulator transition has been observed,…
We carry out Monte Carlo simulations of the uniformly frustrated 3d XY model as a model for vortex line fluctuations in a high Tc superconductor. A density of vortex lines of f=1/25 is considered. We find two sharp phase transitions. The…
Effects of the electron-electron interaction in the two-dimensional flux phase are investigated. We treat the half-filled Hubbard model with a magnetic flux $\pi$ per plaquette by the quantum Monte Carlo method. When the interaction is…
We study the current response of an AC driven dissipative Mott insulator system, a normal quantum dot array, using an analytical Keldysh field theory approach. Deep in the Mott insulator regime, the nonequilibrium steady state (NESS)…
We consider here the fluctuation conductivity near the point of the insulator-superconductor transition in a system of regular Josephson junction arrays in the presence of particle-hole asymmetry or equivalently homogeneous charge…
We investigate the zero-temperature superfluid to insulator transitions in a diluted two-dimensional quantum rotor model with particle-hole symmetry. We map the Hamiltonian onto a classical $(2+1)$-dimensional XY model with columnar…
The superconducting transition in presence of strong columnar disorder parallel to the magnetic field is considered. A solvable model appropriate for description of the broad crossover regime towards the true "glassy" critical behavior is…
In this article, we present evidence for the existence of vortex-solid/glass (VG) to vortex-fluid (VF) transition in a type-II superconductor (SC), NbN. We probed the VG to VF transition in both 2D and 3D films of NbN through studies of…
A square array of Josephson junctions with modulated strength in a magnetic field with half a flux quantum per plaquette is studied by analytic arguments and dynamical simulations. The modulation is such that alternate columns of junctions…
We study the dynamics of current-biased Josephson-junction arrays with a magnetic penetration depth smaller than the lattice spacing. We compare the dynamics imaged by low-temperature scanning electron microscopy to the vortex dynamics…
The dynamic phase diagram of vortex lattices driven in disorder is calculated in two and three dimensions. A modified Lindemann criterion for the fluctuations of the distance of neighboring vortices is used, which unifies previous analytic…
We have studied experimentally the magnetic field-induced superconductor-insulator quantum phase transition in one-dimensional arrays of small Josephson junctions. The zero bias resistance was found to display a drastic change upon…
In type-I superconductors, zero electrical resistivity and perfect diamagnetism define two fundamental criteria for superconducting behavior. In contrast, type-II superconductors exhibit more complex mixed state physics, where magnetic flux…
The Mott critical point between a metal and a correlated insulator has usually been studied via density or spin density bosonic mode fluctuations according to the standard Ginzburg-Landau-Wilson phase transition paradigm. A moment's…
We consider the fluctuation conductivity in the critical region of a disorder induced quantum phase transition in layered d-wave superconductors. We specifically address the fluctuation contribution to the system's conductivity in the limit…