Design and fabrication of meta-cavity for strong coupling investigation

Strong coupling interactions lie at the heart of quantum optics, serving as a cornerstone for advancing light-matter interactions and underpinning transformative technological applications; in this work we aimed at exploring strong light-matter interactions in two-dimensional (2D) crystalline Van der Waals materials coupled to specially designed meta??surface cavities, often referred to as "meta-cavities." The goal is to gain new insights into the physics and material characteristics by designing meta-cavities evaluating their effectiveness in coupling with 2D materials and assessing their potential applications. This project could potentially help investigate the feasibility of experimentally demonstrating the first phonon-polariton condensate (PhP-BEC) by appropriately pumping the hybrid coupled system. To achieve these goals, the theory of Bound States in the Continuum (BIC) was exploited, in order to achieve meta-cavities with exceptionally high-quality factors, which is critical for achieving strong coupling with 2D materials. The study successfully theorized and designed such cavities by exploiting a combination of FEM analysis and RCWA simulations, with the subsequent implementation and optimization of a fabrication process to achieve the aforementioned goals.