Guided Mode Metasurface Assisted Tailored Light-Matter Interactions in Semiconducting Quantum Emitters

Integration of semiconductor colloidal quantum wells (CQWs) with advanced photonic architectures has emerged as a frontier for achieving tailored light-matter interactions and facilitating the efficient transport of energy. Here, we combined CQWs composed of Cadmium Selenide (CdSe) with a guided mode metasurface resonator (MSR), consisting of a periodic arrangement of holes in a square-lattice geometry, fabricated on a SiN slab-waveguide platform. MSR exhibits narrow resonances in both out-of-plane (transmission) and in-plane direction that can be utilized to alter emission response of CQWs. As a result, we observed an enhancement in emission intensity, accompanied by an astounding 95% reduction in linewidth of the out-of-plane emission. Similarly, the in-plane guided emission captured at sample’s edge was found to exhibit a significantly reduced linewidth of 5.67 meV as compared to the natural linewidth of 81.4 meV. Such wavelength selective emission enhancements were realized based on the spectral overlap between the narrow-band MSR response and broader emission from CQWs. These findings were verified by performing finite difference time domain (FDTD) simulations. Further, we also demonstrate long range exciton transport of CQWs upto 1 mm with the assistance of in-plane slab waveguide modes. The propagating excitons were captured by MSR leading to spectrally narrowed out-coupled light, paving the way for construction of on-chip light sources.