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arXiv · 1708.02311

A valley valve and electron beam splitter

Jing Li·Rui-Xing Zhang·Zhenxi Yin·Jianxiao Zhang·Kenji Watanabe·Takashi Taniguchi·Chaoxing Liu·Jun Zhu
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Abstract

Developing alternative paradigms of electronics beyond silicon technology requires the exploration of fundamentally new physical mechanisms, such as the valley specific phenomena in hexagonal two-dimensional materials. We realize ballistic valley Hall kink states in bilayer graphene and demonstrate gate-controlled current transmission in a four-kink router device. The operations of a waveguide, a valve and a tunable electron beam splitter are demonstrated. The valley valve exploits the valley-momentum locking of the kink states and reaches an on/off ratio of 8 at zero magnetic field. A magnetic field enables a full-ranged tunable coherent beam splitter. These results pave the path to building a scalable, coherent quantum transportation network based on the kink states.

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Jing Li, Rui-Xing Zhang, Zhenxi Yin, Jianxiao Zhang, Kenji Watanabe, Takashi Taniguchi, Chaoxing Liu, Jun Zhu. 2017-08-07. A valley valve and electron beam splitter. https://doi.org/10.1126/science.aao5989

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