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arXiv · 2010.15154

Spin-valley collective modes of the electron liquid in graphene

Zachary M. Raines·Vladimir I. Fal'ko·Leonid I. Glazman
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Abstract

We develop the theory of collective modes supported by a Fermi liquid of electrons in pristine graphene. Under reasonable assumptions regarding the electron-electron interaction, all the modes but the plasmon are over-damped. In addition to the $SU(2)$ symmetric spin mode, these include also the valley imbalance modes obeying a $U(1)$ symmetry, and a $U(2)$ symmetric valley spin imbalance mode. We derive the interactions and diffusion constants characterizing the over-damped modes. The corresponding relaxation rates set fundamental constraints on graphene valley- and spintronics applications.

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Zachary M. Raines, Vladimir I. Fal'ko, Leonid I. Glazman. 2021-02-22. Spin-valley collective modes of the electron liquid in graphene. https://doi.org/10.1103/physrevb.103.075422

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