Related papers: Superconducting phase transitions in frustrated Jo…
We study disordered Josephson junctions arrays with long-range interaction and charging effects. The model consists of two orthogonal sets of positionally disordered $N$ parallel filaments (or wires) Josephson coupled at each crossing and…
The nature of decoupling in the mixed phase of extremely type-II layered superconductors is studied theoretically through a duality transformation of the layered XY model with frustration. In the limit of weak coupling, we generally find…
We investigate the influence of quantum fluctuations and weak disorder on the vortex dynamics in a two-dimensional superconducting Berezinskii-Kosterlitz-Thouless system. The temperature below which quantum fluctuations dominate the vortex…
The Josephson equations predict remarkable effects concerning the phase state of a superconducting junction with an oscillating current induced by a static voltage. Whether the paradigm can be twisted by yielding an oscillating voltage…
We present a review of our numerical studies on non equilibrium vortex dynamics in Josephson Junction arrays (JJA) driven by a dc current. Dynamical phase diagrams for different magnetic fields, current directions and varying temperature…
Two-dimensional arrays of ballistic Josephson junctions are important as model systems for synthetic quantum materials. Here, we investigate arrays of multiterminal junctions which exhibit a phase difference $\varphi_0$ at zero current.…
We study the effect of thermal fluctuations in a fully frustrated Josephson junction array driven by a current I larger than the apparent critical current I_c(T). We calculate numerically the behavior of the chiral order parameter of Z_2…
We use the three-dimensional Josephson junction array system as a model for studying the temperature dependence of the c-axis resistivity of high temperature superconductors, in the presence of an external magnetic field H applied in the…
We propose a phase diagram for the vortex structure of high temperature superconductors which incorporates the effects of anisotropy and disorder. It is based on numerical simulations using the three-dimensional Josephson junction array…
The phase diagram of a 2D Josephson junction array with large substrate resistance, described by a quantum XY model, is studied by means of Fourier path-integral Monte Carlo. A genuine Berezinskii-Kosterlitz-Thouless transition is found up…
We have performed large-scale Monte Carlo simulations on a model describing a (2+1)-dimensional array of dissipative Josephson junctions. We find three distinct stable quantum phases of the system. The most ordered state features long-range…
The mixed phase of extremely type-II layered superconductors in perpendicular magnetic field is studied theoretically via the layered XY model with uniform frustration. A partial duality analysis is carried out in the weak-coupling limit.…
We have used Monte Carlo simulations, combined with finite-size scaling and two different real-space renormalization group approaches, to study a fully frustrated three-dimensional XY model on a simple cubic lattice. This model corresponds…
The ground state of the quantum rotor model in two dimensions with random phase frustration is investigated. Extensive Monte Carlo simulations are performed on the corresponding (2+1)-dimensional classical model under the entropic sampling…
Monte Carlo simulations of the frustrated 2D XY model were carried out at small commensurate values of the frustration $f$. For $f=1/30$ a single transition was observed at which phase coherence (finite helicity modulus) and vortex lattice…
We study the dynamics of vortices in strongly disordered $d=2$ Josephson junction arrays and superconducting films driven by a current. We find a dynamic phase transition in vortex flow at a current $I_p>I_c$. Below $I_p$ there is plastic…
The flux line lattice melting transition in two-dimensional pure and disordered superconductors is studied by a Monte Carlo simulation using the lowest Landau level approximation and quasi-periodic boundary condition on a plane. The…
We examine the dynamical consequences of Berry's phase for Josephson junctions, junction arrays, and their vortices. Josephson's equation and the related phase slip voltages are shown to be uneffected by Berry's phase. In an annular…
We investigate the phases and phase-transitions in one-dimensional alternating mixed-spin (1/2-1) chain in the presence of both frustration and anisotropy. Frustration is introduced via next-nearest-neighbor interactions, while single-ion…
In many cases inhomogeneities are known to exist near the metal (or superconductor)- insulator transition, as follows from well-known domain-wall arguments. If the conducting regions are large enough, and if they have superconducting…