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arXiv · 1102.0349

Parallel magnetic field driven quantum phase transition in a thin topological insulator film

A. A. Zyuzin·M. D. Hook·A. A. Burkov
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Abstract

It is well-known that helical surface states of a three-dimensional topological insulator (TI) do not respond to a static in-plane magnetic field. Formally this occurs because the in-plane magnetic field appears as a vector potential in the Dirac Hamiltonian of the surface states and can thus be removed by a gauge transformation of the surface electron wavefunctions. Here we show that when the top and bottom surfaces of a thin film of TI are hybridized and the Fermi level is in the hybridization gap, a nonzero diamagnetic response appears. Moreover, a quantum phase transition occurs at a finite critical value of the parallel field from an insulator with a diamagnetic response to a semimetal with a vanishing response to the parallel field.

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A. A. Zyuzin, M. D. Hook, A. A. Burkov. 2011-06-28. Parallel magnetic field driven quantum phase transition in a thin topological insulator film. https://doi.org/10.1103/physrevb.83.245428

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