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arXiv · 1612.07624

Oscillating magnetoresistance in graphene p-n junctions at intermediate magnetic fields

Hiske Overweg·Hannah Eggimann·Ming-Hao Liu·Anastasia Varlet·Marius Eich·Pauline Simonet·Yongjin Lee·Kenji Watanabe·Takashi Taniguchi·Klaus Richter·Vladimir I. Fal'ko·Klaus Ensslin·Thomas Ihn
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Abstract

We report on the observation of magnetoresistance oscillations in graphene p-n junctions. The oscillations have been observed for six samples, consisting of single-layer and bilayer graphene, and persist up to temperatures of 30 K, where standard Shubnikov-de Haas oscillations are no longer discernible. The oscillatory magnetoresistance can be reproduced by tight-binding simulations. We attribute this phenomenon to the modulated densities of states in the n- and p- regions.

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Hiske Overweg, Hannah Eggimann, Ming-Hao Liu, Anastasia Varlet, Marius Eich, Pauline Simonet, Yongjin Lee, Kenji Watanabe, Takashi Taniguchi, Klaus Richter, Vladimir I. Fal'ko, Klaus Ensslin, Thomas Ihn. 2017-05-18. Oscillating magnetoresistance in graphene p-n junctions at intermediate magnetic fields. https://doi.org/10.1021/acs.nanolett.6b05318

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