Effects of diagonal disorder on Charge Density Wave and Superconductivity in local pair systems

Abstract

We analyse the influence of diagonal disorder (random site energy) on Charge Density Wave (CDW) and Superconductivity (SS) in local pair systems which are described by the model of hard core charged bosons on a lattice. This problem was previously studied within the mean field approximation for the case of half filled band (n = 1). Here we extend that investigation to the case of arbitrary particle concentration (0 < n < 2) and examine the phase diagrams of the model and the behaviour of superfluid density as a function of n and the increasing disorder. Depending on the strength of random on-site energies, the intersite density-density repulsion and the concentration the model can exhibit several various phases, including homogeneous phases: CDW, SS and Bose-glass (NO) as well as the phase separated states: CDW-SS, CDW-NO and particle droplets. The obtained results for SS phase are in qualitative agreement with the available Monte Carlo calculations for two dimensional lattice. Also, in a definite range of parameters the system exhibits the phenomena which we call a disorder induced superconductivity and a disorder induced charge ordering.

arXiv comment21 pages, 8 figures

References in corpus (5)

• The superconductor-insulator transition in 2D dirty boson systems
• Mean Field Theory of the Localization Transition
• Effect of Disorder on Charge Density Wave and Superconducting Order in the Half-Filled Attractive Hubbard Model
• Two-dimensional Superfluidity and Localization in the Hard-Core Boson Model: a Quantum Monte Carlo Study
• Critical Exponents for Three-Dimensional Superfluid--Bose-Glass Phase Transition

Cited by in corpus (5)

• Emergent superconductivity upon disordering a charge density wave ground state
• Real space inhomogeneities in high temperature superconductors: the perspective of two-component model
• Effects of Disorder on Superconductivity of Systems with Coexisting Itinerant Electrons and Local Pairs
• Charge and Phase Fluctuations in Attractive Hubbard Model
• Variations of Pairing Potential and Charge Distribution in Presence of a Non-magnetic Impurity