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arXiv · 1410.6330

Optical conductivity and surface plasmon modes of U(1) spin liquid states with large spinon Fermi surfaces

Yuan-Fei Ma·Tai-Kai Ng
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Abstract

In this paper we study the optical properties of $U(1)$ spin liquids with large spinon Fermi surfaces based on a simple formula for the bulk optical conductivity obtained through the Ioffe-Larkin composition rule. We show that the optical conductivity of $U(1)$ spin liquids at energies above the charge gap has a unique feature that distinguishes them from ordinary insulators. In particular we show the existence of a long-life surface plasmon mode propagating along the interface between a linear medium and the spin liquid at frequencies above the charge gap, which can be detected by the widely used Kretschmann-Raether three-layer configuration.

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Yuan-Fei Ma, Tai-Kai Ng. 2014-10-23. Optical conductivity and surface plasmon modes of U(1) spin liquid states with large spinon Fermi surfaces. https://doi.org/10.1103/physrevb.91.075106

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