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arXiv · 1502.00027

Intrinsic Damping of Collective Spin Modes in a Two-Dimensional Fermi Liquid with Spin-Orbit Coupling

Abstract

A Fermi liquid with spin-orbit coupling (SOC) is expected to support a new kind of collective modes: oscillations of magnetization in the absence of the magnetic field. We show that these modes are damped by the electron-electron interaction even in the limit of an infinitely long wavelength (q = 0). The linewidth of the collective mode is on the order of Δ^2=E_F , where Δ is a characteristic spin-orbit energy splitting and E_F is the Fermi energy. Such damping is in a stark contrast to known damping mechanisms of both charge and spin collective modes in the absence of SOC, all of which disappear at q = 0, and arises because none of the components of total spin is conserved in the presence of SOC.

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Saurabh Maiti, Dmitrii L. Maslov. 2015-01-30. Intrinsic Damping of Collective Spin Modes in a Two-Dimensional Fermi Liquid with Spin-Orbit Coupling. https://doi.org/10.1103/physrevlett.114.156803

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