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arXiv · 1602.06519

Electrical control of intervalley scattering in graphene via the charge state of defects

Baoming Yan·Qi Han·Zhenzhao Jia·Jingjing Niu·Tuocheng Cai·Dapeng Yu·Xiaosong Wu
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Abstract

We study the intervalley scattering in defected graphene by low-temperature transport measurements. The scattering rate is strongly suppressed when defects are charged. This finding highlights "screening" of the short-range part of a potential by the long-range part. Experiments on calcium-adsorbed graphene confirm the role of a long-range Coulomb potential. This effect is applicable to other multivalley systems, provided that the charge state of a defect can be electrically tuned. Our result provides a means to electrically control valley relaxation and has important implications in valley dynamics in valleytronic materials.

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Baoming Yan, Qi Han, Zhenzhao Jia, Jingjing Niu, Tuocheng Cai, Dapeng Yu, Xiaosong Wu. 2016-02-21. Electrical control of intervalley scattering in graphene via the charge state of defects. https://doi.org/10.1103/physrevb.93.041407

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