Deep-Ultraviolet Raman Measurements Using a Spatial Heterodyne Raman Spectrometer (SHRS)

A deep-ultraviolet (UV) 244 nm excitation spatial heterodyne Raman spectrometer (SHRS) is demonstrated for the first time. The deep-UV SHRS has no moving parts, and even though it is small for a deep-UV Raman spectrometer, the spectral resolution is shown to be about 4 cm(-1). The deep-UV SHRS also has a large input aperture and acceptance angle, and the resulting large field of view is shown to be useful to avoid laser-induced sample degradation. In this feasibility study, Raman spectra of several compounds are measured to demonstrate the spectral resolution and range of the system. A photosensitive compound is also measured to demonstrate the use of a large laser spot to minimize UV-laser-induced sample degradation.