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arXiv · 1202.0821

Ordered Loop Current States in Bilayer Graphene

Lijun Zhu·Vivek Aji·Chandra M. Varma
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Abstract

While single-layer graphene shows extraordinary phenomena which are stable against electronic interactions, the non-interacting state of bilayer graphene is unstable to infinitesimal interactions leading to one of many possible exotic states. Indeed a gapped state is found in experiments but none of the states proposed so far can provide full accounts of its properties. Here we show that a magnetoelectric (ME) state is consistent with the experimental observations. This state breaks time-reversal symmetry through a pair of spontaneously generated current loops in each layer, and has odd-parity with respect to the two layers. We also suggest further experiments to check whether the ME state is indeed the gapped state found in experiments.

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Lijun Zhu, Vivek Aji, Chandra M. Varma. 2013-02-06. Ordered Loop Current States in Bilayer Graphene. https://doi.org/10.1103/physrevb.87.035427

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