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arXiv · 1312.1164

Bilayer graphene Hall bar with a pn-junction

S. P. Milovanovic·M. Ramezani Masir·F. M. Peeters
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Abstract

We investigate the magnetic field dependence of the Hall and the bend resistances for a ballistic Hall bar structure containing a pn-junction sculptured from a bilayer of graphene. The electric response is obtained using the billiard model and we investigate the cases of bilayer graphene with and without a band gap. Two different conduction regimes are possible: $i$) both sides of the junction have the same carrier type, and $ii$) one side of the junction is n-type while the other one is p-type. The first case shows Hall plateau-like features in the Hall resistance that fade away as the band gap opens. The second case exhibits a bend resistance that is asymmetric in magnetic field as a consequence of snake states along the pn-interface, where the maximum is shifted away from zero magnetic field.

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S. P. Milovanovic, M. Ramezani Masir, F. M. Peeters. 2013-12-04. Bilayer graphene Hall bar with a pn-junction. https://doi.org/10.1063/1.4821264

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