Exceptional points treatment of cavity spectroscopies

Shaul Mukamel; Anqi Li; Michael Galperin

doi:10.1063/5.0142022

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arXiv · 2304.13641

Exceptional points treatment of cavity spectroscopies

Shaul Mukamel·Anqi Li·Michael Galperin

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Abstract

The infrared response of a system of two vibrational modes in a cavity is calculated by an effective non-Hermitian Hamiltonian derived by employing the nonequilibrium Green's functions (NEGF) formalism. Degeneracies of the Hamiltonian (exceptional points, EP) widely employed in theoretical analysis of optical cavity spectroscopies are used in an approximate treatment and compared with the full NEGF. Qualitative limitations of the EP treatment are explained by examining the approximations employed in the calculation.

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Shaul Mukamel, Anqi Li, Michael Galperin. 2023-04-26. Exceptional points treatment of cavity spectroscopies. https://doi.org/10.1063/5.0142022

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