Hyperspectral photoluminescence and reflectance microscopy of 2D materials

Optical micro-spectroscopy is an invaluable tool for studying and characterizing samples ranging from classical semiconductors to low-dimensional materials and heterostructures. To date, most implementations are based on point-scanning techniques, which are flexible and reliable, but slow. Here, we describe a setup for highly parallel acquisition of hyperspectral reflection and photoluminescence (PL) microscope images using a push-broom technique. Spatial as well as spectral distortions are characterized and their digital corrections are presented. We demonstrate close- to diffraction-limited spatial imaging performance and a spectral resolution limited by the spectrograph. The capabilities of the setup are demonstrated by recording a hyperspectral PL map of a MoSe2-WSe2 lateral heterostructure, grown by chemical vapor deposition (CVD), from which we extract the luminescence energies, intensities and peak widths across the interface.