Quantum Many-Body Theory for Exciton-Polaritons in Semiconductor Mie Resonators in the Non-Equilibrium

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Quantum Many-Body Theory for Exciton-Polaritons in Semiconductor Mie Resonators in the Non-Equilibrium

Authors: Andreas Lubatsch and Regine Frank

Appl. Sci. 2020, 10(5), 1836; https://doi.org/10.3390/app10051836

Special Issue Light Matter Interaction at Nanoscale: What Matters Most

Editors: Vladimir P. Drachev and Allan D. Boardman

Abstract: We implement externally excited ZnO Mie resonators in a framework of a generalized Hubbard Hamiltonian to investigate the lifetimes of excitons and exciton-polaritons out of thermodynamical equilibrium. Our results are derived by a Floquet-Keldysh-Green's formalism with Dynamical Mean Field Theory (DMFT) and a second order iterative perturbation theory solver (IPT). We find that the Fano resonance which originates from coupling of the continuum of electronic density of states to the semiconductor Mie resonator yields polaritons with lifetimes between 0.6 ps and 1.45 ps. These results are compared to ZnO polariton lasers and to ZnO random lasers. We interpret the peaks of the exciton-polariton lifetimes in our results as a sign of gain narrowing which may lead to stable polariton lasing modes in the single excited ZnO Mie resonator. This form of gain may lead to polariton random lasing in an ensemble of ZnO Mie resonators in the non-equilibrium.

Keywords: Mie resonance; Fano resonance; Floquet modes; Stark effect; exciton; polariton; semiconductors; nano-structures; lasers; dynamical mean field theory; complex media; non-equilibrium