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arXiv · 1210.0907

Quantum Phase Transition between Integer Quantum Hall States of Bosons

Tarun Grover·Ashvin Vishwanath
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Abstract

Bosonic Integer Quantum Hall (IQH) phases are a class of symmetry protected topological (SPT) phases that, similar to the fermionic IQH states, support a quantized Hall conductance. They, however, require interactions for their realization. Here we study quantum Hall plateau transitions between a trivial insulator and a bosonic IQH phase, in a clean system. Generically, we find an intervening superfluid phase. The presence of additional symmetries, however, can potentially lead to a direct transition between these phases. We employ a fermionic parton description that captures both the insulating phases as well as the transition between them. The critical theory is massless QED-3 with Nf = 2 fermion flavors. The fermions have a surprisingly simple interpretation - they are vortices of the superfluid. Therefore the universal conductivity at the transition, assuming it is continuous, equals the universal resistivity of Dirac fermions in QED-3. We also briefly comment on sigma model descriptions of the transition and the surface states of related 3D SPT phases.

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Tarun Grover, Ashvin Vishwanath. 2012-10-02. Quantum Phase Transition between Integer Quantum Hall States of Bosons. https://doi.org/10.1103/physrevb.87.045129

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