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arXiv · 0711.2070

The insulating phases and superfluid-insulator transition of disordered boson chains

Abstract

Using a strong disorder real-space renormalization group (RG), we study the phase diagram of a fully disordered chain of interacting bosons. Since this approach does not suffer from run-away flows, it allows a direct study of the insulating phases, which are not accessible in a weak disorder perturbative treatment. We find that the universal properties of the insulating phase are determined by the details and symmetries of the onsite chemical-potential disorder. Three insulating phases are possible: (i) an incompressible Mott glass with a finite superfluid susceptibility, (ii) a random-singlet glass with diverging compressibility and superfluid susceptibility, (iii) a Bose glass with a finite compressibility but diverging superfluid susceptibility. In addition to characterizing the insulating phases, we show that the superfluid-insulator transition is always of the Kosterlitz-Thouless universality class.

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BibTeXRIS

Ehud Altman, Yariv Kafri, Anatoli Polkovnikov, Gil Refael. 2007-11-13. The insulating phases and superfluid-insulator transition of disordered boson chains. https://doi.org/10.1103/physrevlett.100.170402

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