Characterization of monolayer WSe₂ sandwiched in a hetero-plasmonic dimer

Abstract

Recent interests in layered transition-metal dichalcogenides (TMDCs), such as WSe2, MoS2, etc., arise due to their attractive electrical, optical, and mechanical properties with potential applications in energy storage, generation, and many more. Embedding these 2D materials in plasmonic cavities can further enhance light-matter interactions and alter their properties, resulting in diverse and efficient optoelectronic applications. The strain due to the geometry and charge transfer due to the plasmonic materials can further modify the TMDCs’ optical response for sensing applications and as single photon emitters in on-chip optoelectronic applications. This work discusses one such 2D-plasmonic hybrid configuration of a silver sphere on a gold disc with WSe2 sandwiched in between. We perform non-invasive Raman and PL studies of this system to estimate the field enhancement and discuss strain and doping induced in the TMDC.