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Effect of orbital currents on the restricted optical sum rule

L. Benfatto·S. G. Sharapov·H. Beck
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Abstract

We derive the restricted optical-conductivity sum rule for a model with circulating orbital currents. It is shown that an unusual coupling of the vector potential to the interaction term of the model Hamiltonian results in a non-standard form of the sum rule. As a consequence, the temperature dependence of the restricted spectral weight could be compatible with existing experimental data for high-$T_c$ cuprates above the critical temperature $T_c$. We extend our results to the superconducting state, and comment on the differences and analogies between these two symmetry-breaking phenomena.

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L. Benfatto, S. G. Sharapov, H. Beck. 2004-06-07. Effect of orbital currents on the restricted optical sum rule. https://doi.org/10.1140/epjb%2Fe2004-00219-5

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