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arXiv · 1512.05971

Chiral and Non-Chiral Edge States in Quantum Hall Systems with Charge Density Modulation

Paweł Szumniak·Jelena Klinovaja·Daniel Loss
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Abstract

We consider a system of weakly coupled wires with quantum Hall effect (QHE) and in the presence of a spatially periodic modulation of the chemical potential along the wire, equivalent to a charge density wave (CDW). We investigate the competition between the two effects which both open a gap. We show that by changing the ratio between the amplitudes of the CDW modulation and the tunneling between wires, one can switch between non-topological CDW-dominated phase to topological QHE-dominated phase. Both phases host edge states of chiral and non-chiral nature robust to on-site disorder. However, only in the topological phase, the edge states are immune to disorder in the phase shifts of the CDWs. We provide analytical solutions for filling factor $ν=1$ and study numerically effects of disorder as well as present numerical results for higher filling factors.

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Paweł Szumniak, Jelena Klinovaja, Daniel Loss. 2015-12-18. Chiral and Non-Chiral Edge States in Quantum Hall Systems with Charge Density Modulation. https://doi.org/10.1103/physrevb.93.245308

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