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arXiv · 2404.01027

Easy-to-configure zero-dimensional valley-chiral modes in a graphene point junction

Konstantin Davydov·Xi Zhang·Wei Ren·Matthew Coles·Logan Kline·Bryan Zucker·Kenji Watanabe·Takashi Taniguchi·Ke Wang
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Abstract

The valley degree of freedom in 2D materials can be manipulated for low-dissipation quantum electronics called valleytronics. At the boundary between two regions of bilayer graphene with different atomic or electrostatic configuration, valley-polarized current has been realized. However, the demanding fabrication and operation requirements limit device reproducibility and scalability toward more advanced valleytronics circuits. We demonstrate a new device architecture of a point junction where a valley-chiral 0D PN junction is easily configured, switchable, and capable of carrying valley current with an estimated polarization of ~80%. This work provides a new building block in manipulating valley quantum numbers and scalable valleytronics.

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Konstantin Davydov, Xi Zhang, Wei Ren, Matthew Coles, Logan Kline, Bryan Zucker, Kenji Watanabe, Takashi Taniguchi, Ke Wang. 2024-04-01. Easy-to-configure zero-dimensional valley-chiral modes in a graphene point junction. https://arxiv.org/abs/2404.01027

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