Tunable strong plasmon-exciton coupling based on borophene and deep subwavelength perovskite grating

TL;DR

This paper demonstrates a tunable strong plasmon-exciton coupling system using borophene and perovskite grating, achieving significant Rabi splitting and active phase modulation for advanced plasmonic device applications.

Contribution

It introduces a diffraction-unlimited borophene-perovskite system with electrically tunable strong coupling and active phase control, advancing the design of miniaturized plasmonic devices.

Findings

Achieved up to 230 meV Rabi splitting under zero-detuning.

Demonstrated active phase modulation with a 1.76π range.

Observed parity-time symmetry breaking by adjusting layer distance.

Abstract

Two-dimensional materials support deeply confined and tunable plasmonic modes, which have great potential for achieving device miniaturization and flexible manipulation. In this paper, we propose a diffraction-unlimited system composed of borophene layer and perovskite grating to investigate the strong coupling between the borophene guiding plasmon (BGP) and perovskite exciton (PE) mode. The resonant energy of BGP mode could be electrically tuned to match the energy of PE mode, and a remarkable Rabi splitting is attained under zero-detuning condition. The splitting energy could reach 230 meV due to the strong field enhancement provided by BGP mode. Consequently, an active reflective phase modulation with 1.76{\pi} range is achieved by dynamically manipulating the detuning. Furthermore, by increasing the distance between the borophene layer and perovskite grating, a parity-time symmetry breaking could be observed with the vanished energy splitting. Our results deepen the understanding of light-matter interaction at the sub-wavelength scale and provide a guideline for designing active plasmonic devices.