Nanoimprinted pyramid scanning probe for near-field optical mapping

Scanning near-field optical microscope (SNOM) can simultaneously collect an optical spectrum and topographic information at a spatial resolution beyond the diffraction limit which provides critical insight into understanding how local material properties and structure result in the macroscopic functionality of a material. In the meantime, SNOM enables selective enhancement of the light emission through plasmonic design and nanofabrication on the scanning probe. This work aims at developing a new type of near-field probe using a low-cost and high-throughput nanoimprinting technique for the optical study of low-dimensional quantum materials. The performance of the nanoimprinted probe was demonstrated by high height sensing and high-resolution optical mapping on a 2-dimensional (2D) semiconductor and 0D luminescent nanocrystals. Based on the pyramid probe, we designed and fabricated several near-field configurations for the study of excitonic properties in 2D material including polarization-controlled emission, dark exciton, as well as strong exciton-plasmon coupling.