The Superconductor-insulator Transition in 2d Dirty Boson Systems Typeset Using Revt E X 1
نویسندگان
چکیده
Universal properties of the zero temperature superconductor-insulator transition in two-dimensional amorphous films are studied by extensive Monte Carlo simulations of bosons in a disordered medium. We report results for both short-range and long-range Coulomb interactions for several different points in parameter space. In all cases we observe a transition from a superconducting phase to an insulating Bose glass phase. From finite-size scaling of our Monte Carlo data we determine the universal conductivity σ∗ and the critical exponents at the transition. The result σ∗ = (0.55 ± 0.06)(2e)2/h for bosons with long-range Coulomb interaction is roughly consistent with experiments reported so far. We also find σ∗ = (0.14±0.03)(2e)2/h for bosons with short-range interactions. PACS numbers: 74.65.+n, 74.70.Mq, 74.75.+t Typeset using REVTEX
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