Tailoring Light Emission and Scattering from Atomically Thin Materials with Transferable Nanostructures

Optical spectroscopy is indispensable for unveiling the unique properties and symmetries of materials in the atomically thin limit. However, the vanishing thickness often leads to a cross section too low for conventional optical methods to work. In this work, we developed a technique, completely dry and simple to implement, to fabricate and transfer high-resolution optical enhancement nanostructures for Raman and PL spectroscopy. We demonstrate orders-of-magnitude increase in the intensities of single-layer WSe2 phonon modes;enabling the detection of three-layer NiI2 phonon modes using 785 nm laser excitation; and selective Purcell enhancement of the quenched excitons in WSe2/MoS2 heterostructures. We also highlight that the method is particularly suitable for optical studies of air-sensitive materials, as the fabrication and transfer can be performed in situ.