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arXiv · 1511.03044

Gate tuneable beamsplitter in ballistic graphene

Peter Rickhaus·Péter Makk·Ming-Hao Liu·Klaus Richter·Christian Schönenberger
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Abstract

We present a beam splitter in a suspended, ballistic, multiterminal, bilayer graphene device. By using local bottomgates, a p-n interface tilted with respect to the current direction can be formed. We show that the p-n interface acts as a semi-transparent mirror in the bipolar regime and that the reflectance and transmittance of the p-n interface can be tuned by the gate voltages. Moreover, by studying the conductance features appearing in magnetic field, we demonstrate that the position of the p-n interface can be moved by $1\,μ$m. The herein presented beamsplitter device can form the basis of electron-optic interferometers in graphene.

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Peter Rickhaus, Péter Makk, Ming-Hao Liu, Klaus Richter, Christian Schönenberger. 2015-11-12. Gate tuneable beamsplitter in ballistic graphene. https://doi.org/10.1063/1.4938073

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