Electrically tunable dipolar polaritons with giant nonlinearity in a homobilayer microcavity

TL;DR

This paper demonstrates electrically tunable dipolar polaritons in a bilayer MoS2 microcavity, achieving a sevenfold increase in nonlinearity and enabling control over light-matter interactions for advanced photonic applications.

Contribution

It introduces a novel electrically tunable platform for dipolar polaritons in TMD homobilayers, with giant, adjustable nonlinearities and independent control of coupling regimes.

Findings

Giant polariton-polariton interaction strength tunable by a factor of seven.

In situ reshaping of dispersion and modulation of light-matter coupling via electric field.

Switching between strong and weak coupling regimes using electrostatic doping.

Abstract

Active control over strong optical nonlinearity in solid-state systems is central to unlocking exotic many-body phenomena and scalable photonic devices. While exciton-polaritons in transition metal dichalcogenides (TMDs) offer a promising platform, their practical utility is often impeded by fixed interaction parameters and an intrinsic trade-off between nonlinearity and oscillator strength. Here, we report electrically tunable dipolar polaritons in a dual-gated bilayer MoS2 microcavity, demonstrating in situ reshaping of the dispersion and modulation of the light-matter coupling strength via the quantum-confined Stark effect. Crucially, this architecture enables a giant polariton-polariton interaction strength tunable by a factor of seven. This nonlinearity enhancement arises from a synergistic interplay, in which the electric field amplifies the microscopic dipolar repulsion while simultaneously optimizing the macroscopic excitonic Hopfield coefficient. Furthermore, electrostatic doping serves as an independent control knob to switch the system between strong and weak coupling regimes. Our findings bridge the gap between strong optical coupling and giant dipolar nonlinearities, establishing the TMD homobilayer as a versatile platform for engineering programmable correlated many-body states on a chip.