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arXiv · 1608.05132

A gate-variable spin current demultiplexer based on graphene

Li Su·Xiaoyang Lin·Youguang Zhang·Arnaud Bournel·Yue Zhang·Jacques-Olivier Klein·Weisheng Zhao·Albert Fert
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Abstract

Spintronics, which utilizes spin as information carrier, is a promising solution for nonvolatile memory and low-power computing in the post-Moore era. An important challenge is to realize long distance spin transport, together with efficient manipulation of spin current for novel logic-processing applications. Here, we describe a gate-variable spin current demultiplexer (GSDM) based on graphene, serving as a fundamental building block of reconfigurable spin current logic circuits. The concept relies on electrical gating of carrier density dependent conductivity and spin diffusion length in graphene. As a demo, GSDM is realized for both single-layer and bilayer graphene. The distribution and propagation of spin current in the two branches of GSDM depend on spin relaxation characteristics of graphene. Compared with Elliot-Yafet spin relaxation mechanism, D'yakonov-Perel mechanism results in more appreciable gate-tuning performance. These unique features of GSDM would give rise to abundant spin logic applications, such as on-chip spin current modulators and reconfigurable spin logic circuits.

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Li Su, Xiaoyang Lin, Youguang Zhang, Arnaud Bournel, Yue Zhang, Jacques-Olivier Klein, Weisheng Zhao, Albert Fert. 2016-08-17. A gate-variable spin current demultiplexer based on graphene. https://doi.org/10.1103/physrevapplied.8.034006

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