Delocalization in two dimensional disordered Bose systems and depinning transition in the vortex state in superconductors

Abstract

We investigate two-dimensional Bose system with the long range interactions in the presence of disorder. Formation of the bound states at strong impurity sites gives rise to an additional depletion of the superfluid density. We demonstrate the existence of the intermediate superfluid state where the condensate and localized bosons present simultaneously. We find that interactions suppress localization and that with the increase of the boson density the system experiences a sharp delocalization crossover into a state where all bosons are delocalized. We map our results onto the three dimensional system of vortices in type II superconductors in the presence of columnar defects; the intermediate superfluid state maps to an intermediate vortex liquid where vortex liquid neighbors pinned vortices. We predict the depinning transition within the vortex liquid and depinning induced vortex lattice/Bose glass melting.

References in corpus (4)

• Effects of Disorder in a Dilute Bose Gas
• Thermodynamics of the superfluid dilute Bose gas with disorder
• Melting of 'porous' vortex matter
• Entropy, vortex interactions, and the phase diagram of heavy-ion irradiated Bi_2Sr_2CaCu_2O_8

Cited by in corpus (9)

• Mott insulator phases and first-order melting in BSCCO crystals with periodic surface holes
• Vortex nanoliquid in high-temperature superconductors
• Langevin simulations of the out-of-equilibrium dynamics of the vortex glass in high-temperature superconductors
• Melting and structure of the vortex solid in strongly anisotropic layered superconductors with random columnar pins
• Phase diagram of the vortex system in layered superconductors with strong columnar pinning
• On the melting of the nanocrystalline vortex matter in high-temperature superconductors
• Competitive localization of vortex lines and interacting bosons
• Langevin Dynamics of the vortex matter two-stage melting transition in Bi_2Sr_2CaCu_2O${}_{8+\delta }$ in the presence of straight and of tilted columnar defects
• Monte Carlo Simulation of the Crossover from Bose Glass to Bragg Glass Phase in Layered BSCCO with Columnar Defects