Tuning polariton lasing with phase-gradient plasmonic lattices

Polariton lasing exploiting exciton-photon strong coupling offers a unique approach to realize energy-efficient coherent emission. Precise control of lasing beams is key to advancing optical technologies, but fine-tuning emitters at nanoscale is challenging, and current Fabry-Pérot type microcavities lack flexibility for modifications. This talk will describe an approach to leverage geometric phase gradients in diffractively coupled plasmonic nanoparticle lattices as the cavity design for polariton generation. We combine the array with CdSe nanoplatelets of high oscillator-strength and optical gain, enabling polariton lasing emission with low thresholds. By altering the nanoparticle assembly, we demonstrate the ability to tailor directionality, polarization, and beam profile. These results exhibit a pathway to unlock new degrees of freedom in redistributing polariton energy and offer a compact and versatile platform for next-generation photonic devices.