Bardasis-Schrieffer polaritons in excitonic insulators

Zhiyuan Sun; Andrew J. Millis

doi:10.1103/physrevb.102.041110

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arXiv · 2003.02997

Bardasis-Schrieffer polaritons in excitonic insulators

Zhiyuan Sun·Andrew J. Millis

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Abstract

Bardasis-Schrieffer modes in superconductors are fluctuations in subdominant pairing channels, e.g., d-wave fluctuations in an s-wave superconductor. This Rapid Communication shows that these modes also generically occur in excitonic insulators. In s-wave excitonic insulators, a p-wave Bardasis-Schrieffer mode exists below the gap energy, is optically active and hybridizes strongly with photons to form Bardasis-Schrieffer polaritons, which are observable in both far-field and near-field optical experiments.

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Zhiyuan Sun, Andrew J. Millis. 2020-03-06. Bardasis-Schrieffer polaritons in excitonic insulators. https://doi.org/10.1103/physrevb.102.041110

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