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Optical conductivity of one-dimensional Mott insulators

Davide Controzzi·Fabian H. L. Essler·Alexei M. Tsvelik
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Abstract

We calculate the optical conductivity of one-dimensional Mott insulators at low energies using a field theory description. The square root singularity at the optical gap, characteristic of band insulators, is generally absent and appears only at the Luther-Emery point. We also show that only few particle processes contribute significantly to the optical conductivity over a wide range of frequencies and that the bare perturbative regime is recovered only at very large energies. We discuss possible applications of our results to quasi one-dimensional organic conductors.

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Davide Controzzi, Fabian H. L. Essler, Alexei M. Tsvelik. 2000-08-29. Optical conductivity of one-dimensional Mott insulators. https://doi.org/10.1103/physrevlett.86.680

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