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arXiv · 2109.10168

Optical amplification in a CDW-phase of a quasi-two dimensional material

Stephan Michael·Hans Christian Schneider
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Abstract

We study theoretically the quenching of a charge-density-wave phase in a model system of a quasi-two dimensional material, which includes both electron-hole and electron-phonon interactions leading, respectively to excitonic and coherent-phonon contributions. We discuss how interaction processes affect anomalous expectation values and present a microscopic dynamical picture of the quenching of the phase. We use projection techniques to illustrate the time-dependent appearance of additional bands and anomalous expectation values. We propose an optical amplification effect with a high modulation frequency in the mid-infrared regime.

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Stephan Michael, Hans Christian Schneider. 2021-09-21. Optical amplification in a CDW-phase of a quasi-two dimensional material. https://doi.org/10.1103/physrevb.105.235108

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