Strong coupling between quasi-bound states in the continuum and molecular vibrations in the mid-infrared

Abstract Strong light–matter coupling is of much interest for both fundamental research and technological applications. The recently studied bound state in the continuum (BIC) phenomenon photonics with controlled radiation loss rate significantly facilitates realization strong effect. In this work, we report experimental observation room temperature between quasi-BIC resonances supported by a zigzag metasurface array germanium elliptical disks vibrational resonance polymethyl methacrylate (PMMA) molecules mid-infrared. Based on approach tuning changing thickness coated PMMA layer, can easily observe phenomenon, manifested significant spectral splitting typical anti-crossing behaviors transmission spectrum, distance two hybrid photon-vibration larger than bandwidth absorption line. Our results demonstrate that use all-dielectric nanostructures provides an effective convenient