Room-temperature strong coupling at the nanoscale achieved by inverse design

TL;DR

This paper presents an inverse design methodology to create plasmonic nanostructures that achieve strong light-matter coupling at room temperature, enabling enhanced quantum and classical optical interactions.

Contribution

The authors develop a novel inverse design approach based on an overlap-integral metric to optimize nanostructures for strong coupling with monolayer semiconductors.

Findings

Experimental demonstration of large Rabi splitting in designed nanoantennas

Theoretically optimized configurations for various nanostructures

Pathway to maximize light-matter interactions in integrated platforms

Abstract

Room-temperature strong coupling between plasmonic nanocavities and monolayer semiconductors is a prominent path towards efficient, integrated light-matter interactions. However, designing such systems is challenging due to the nontrivial dependence of the strong coupling on various properties of the cavity and emitter, as well as the subwavelength scale of the interaction. In this work, we develop a methodology for obtaining hybrid nanostructures consisting of plasmonic metasurfaces coupled to atomically thin WS2 layers, exhibiting extreme values of Rabi splitting, by inverse design of the near-field plasmonic response. Contrary to common measures such as the quality factor or the mode volume, our method relies on an overlap-integral-based metric. We experimentally measure large values of Rabi splitting for our nanoantenna designs, while providing theoretically optimal configurations for several additional types of nanostructures. Our results open a path to maximizing light-matter interactions in integrated platforms, for classical and quantum-optical applications.