Generation of Rabi frequency radiation using exciton-polaritons

TL;DR

This paper explores how exciton-polaritons in semiconductor microcavities can be used to generate a broad spectrum of radiation, including infrared and terahertz, through a process similar to difference-frequency generation, with significant enhancement in irradiance.

Contribution

It demonstrates the potential of exciton-polaritons in microcavities for efficient, tunable radiation generation across a wide spectrum, with detailed predictions for organic and inorganic structures.

Findings

Predicted a 280-fold irradiance enhancement in organic microcavities.

Achieved an 8800-fold enhancement in inorganic GaAs microcavities.

High wavelength tunability and relaxed design constraints observed.

Abstract

We study the use of exciton-polaritons in semiconductor microcavities to generate radiation spanning the infrared to terahertz regions of the spectrum by exploiting transitions between upper and lower polariton branches. The process, which is analogous to difference-frequency generation (DFG), relies on the use of semiconductors with a nonvanishing second-order susceptibility. For an organic microcavity composed of a nonlinear optical polymer, we predict a DFG irradiance enhancement of $2.8\cdot10^2$, as compared to a bare nonlinear polymer film, when triple resonance with the fundamental cavity mode is satisfied. In the case of an inorganic microcavity composed of (111) GaAs, an enhancement of $8.8\cdot10^3$ is found, as compared to a bare GaAs slab. Both structures show high wavelength tunability and relaxed design constraints due to the high modal overlap of polariton modes.