Non-equilibrium Optical Conductivity: General Theory and Application to Transient Phases

Dante M. Kennes; Eli Y. Wilner; David R. Reichman; Andrew J. Millis

doi:10.1103/physrevb.96.054506

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arXiv · 1703.07248

Non-equilibrium Optical Conductivity: General Theory and Application to Transient Phases

Dante M. Kennes·Eli Y. Wilner·David R. Reichman·Andrew J. Millis

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Abstract

A non-equilibrium theory of optical conductivity of dirty-limit superconductors and commensurate charge density wave is presented. We discuss the current response to different experimentally relevant light-field probe pulses and show that a single frequency definition of the optical conductivity $\sigma(\omega)\equiv j(\omega)/E(\omega)$ is difficult to interpret out of the adiabatic limit. We identify characteristic time domain signatures distinguishing between superconducting, normal metal and charge density wave states. We also suggest a route to directly address the instantaneous superfluid stiffness of a superconductor by shaping the probe light field.

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Dante M. Kennes, Eli Y. Wilner, David R. Reichman, Andrew J. Millis. 2017-03-21. Non-equilibrium Optical Conductivity: General Theory and Application to Transient Phases. https://doi.org/10.1103/physrevb.96.054506

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