A universal and stable metasurface for photonic quasi bound state in continuum coupled with two dimensional semiconductors

TL;DR

This paper presents a universal, stable metasurface cavity design that can strongly couple with various two-dimensional TMDC semiconductors, addressing fabrication tolerance and enabling consistent strong coupling across different materials.

Contribution

The study introduces a single cavity architecture compatible with four common TMDCs and analyzes fabrication tolerances affecting strong coupling with photonic quasi-BICs.

Findings

A universal cavity design for multiple TMDCs

Analysis of fabrication imperfections on coupling strength

Enhanced understanding of fabrication tolerances

Abstract

Strong coupling of excitons to optical cavity modes is of immense importance to understanding the fundamental physics of quantum electrodynamics at the nanoscale as well as for practical applications in quantum information technologies. There have been several attempts at achieving strong coupling between excitons in two dimensional semiconductors such as transition metal dichalcogenides (TMDCs) and photonic quasi-bound states in the continuum (BICs). We identify two gaps in the platforms for achieving strong coupling between TMDC excitons and photonic quasi-BICs: firstly, in the studies so far, different cavity architectures have been employed for coupling to different TMDCs. This would mean that typically, the fabrication process flow for the cavities will need to be modified as one moves from one TMDC to the other, which can limit the technological progress in the field. Secondly, there has been no discussion of the impact of fabrication imperfections in the studies on strong coupling of these subsystems so far. In this work, we address these two questions by optimizing a cavity with the same architecture which can couple to the four typical TMDCs (MoS$_2$, WS$_2$, MoSe$_2$, WSe$_2$) and perform a detailed investigation on the fabrication tolerance of the associated photonic quasi-BICs and their impact on strong coupling.