相关论文: Quantum Glass Transition in a Periodic Long-Range …
We present an analytic study of a periodic Josephson array with long-range interactions in a transverse magnetic field. We find that this system exhibits a first-order transition into a phase characterized by an extensive number of states…
We present an analytic study of a dynamical instability in a periodic long-range Josephson array frustrated by a weak transverse field. This glass transition is characterized by a diverging relaxation time and a jump in the Edwards-Anderson…
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…
A vortex-glass transition due to point disorder in layered superconductors is studied for the case with an applied field {\it parallel} to the layers. Our calculation of tilt responses indicates that, irrespective of the magnitude of the…
We have studied the magnetic-field-driven quantum phase transitions in Josephson junction arrays with a large coordination number. The characteristic energies were extracted in both the superconducting and insulating phases by integrating…
Quantum-phase transitions in two layers of ultrasmall Josephson junctions, coupled capacitively with each other, are investigated. As the interlayer capacitance is increased, the system at zero temperature is found to exhibit an…
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,…
The electric conductivities in glass phases of three-dimensional (3D) granular superconductors in magnetic fields are examined based on a quantum disordered Josephson-junction array. A correct inclusion of the Ohmic dissipative dynamics…
We study numerically the interplay of phase coherence and vortex-glass state in two-dimensional Josephson-junction arrays with average rational values of flux quantum per plaquette $f$ and random dilution of junctions. For $f=1/2$, we find…
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…
Phase transitions of a flux lattice in layered superconductors with magnetic field perpendicular to the layers and in presence of disorder are studied. We find that the Josephson coupling between layers leads to a strongly pinned Josephson…
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…
When a Josephson junction array is built with hybrid superconductor/metal/superconductor junctions, a quantum phase transition from a superconducting to a two-dimensional (2D) metallic ground state is predicted to happen upon increasing the…
History-dependence and ageing are studied in the low-temperature glass phase of a long-range periodic Josephson array. This model is characterized by two parameters, the number of wires ($2N$) and the flux per unit strip ($\alpha$); in the…
We investigate the quantum phase transition in a one-dimensional chain of ultra-small superconducting grains, considering both the self- and junction capacitances. At zero temperature, the system is transformed into a two-dimensional system…
Disordered superconductors in low dimensions provide an exemplary manifestation for the role of quantum fluctuations in a many-body system. Specifically in Josephson arrays with comparable Josephson and charging energies ($E_J\sim E_C$),…
We investigate the ground state of the irrationally frustrated Josephson junction array with controlling anisotropy parameter \lambda\ that is the ratio of the longitudinal Josephson coupling to the transverse one. We find that the ground…
Josephson junctions translate quantum phase coherence into an electrical response and underpin superconducting sensors and quantum circuits. In conventional junctions, the barrier acts primarily as a passive weak link, however, when the…
We consider interacting vortices in a quasi-one-dimensional array of Josephson junctions with small capacitance. If the charging energy of a junction is of the order of the Josephson energy, the fluctuations of the superconducting order…
We study the quantum phase transitions in two-dimensional arrays of Josephson-couples junctions with short range Josephson couplings (given by the Josephson energy) and the charging energy. We map the problem onto the solvable quantum…