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Dual superfluid-Bose glass critical point in two dimensions and the universal conductivity

Igor F. Herbut
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Abstract

We study the continuum version of the dual theory for a system of two-dimensional, zero temperature, disordered bosons, interacting with short range repulsion and at a commensurate density. The dual theory, which describes vortices in the bosonic ground state, and has a form of 3D classical scalar electrodynamics in random, correlated magnetic field, admits a new disordered critical point within RG calculation at fixed dimension. The universal conductivity and the critical exponents at the superfluid-Bose glass critical point are calculated as series in fixed-point values of the dual coupling constants, to the lowest non-trivial order: $σ_c = 0.25 (2e)^2 /h$, $ν=1.38$ and $z=1.93$. The comparison with numerical results and experiments is discussed.

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Igor F. Herbut. 1997-10-30. Dual superfluid-Bose glass critical point in two dimensions and the universal conductivity. https://doi.org/10.1103/physrevlett.79.3502

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