S&I Spectroscopy & Imaging, a developer of high-performance spectrometers, has announced that it has qualified the C-WAVE tunable laser from Hübner Photonics for use with their TriVista spectrometer system. The combination of these widely tunable, continuous-wave (cw) single frequency lasers (covering wavelengths from 450 nm up to 3.5 µm) with the triple-grating spectrometer TriVista is expected to become a new standard for resonance Raman spectroscopy and microscopy.

“We are delighted to work with S&I in order to help them advance the state of the art in resonance Raman spectrometers. The TriVista spectrometer with its exceptional resolution, sensitivity, and linearity over wide spectral ranges is a powerful instrument that revealed deep insights about the C-WAVE’s spectral performance,” says Korbinian Hens, chief operating officer and R&D manager at Hübner Photonics Kassel.

“The combination of the TriVista spectrometer with the C-WAVE is a powerful and flexible solution for resonant spectroscopy methods, especially for the challenging low-frequency Raman range <10 cm^–1. The extremely narrow linewidth and very stable emission frequency of the laser paired with its outstanding spectral purity allows the recording of impressive Raman spectra: we were able to measure low frequency Raman bands at or below 5 cm^-1 from the excitation wavelength even without filtering the excitation beam,” says Nils Timpe, head of sales at S&I.

For applications in Raman spectroscopy, most tunable lasers require elaborate filtering to suppress unwanted amplified spontaneous emission (ASE) which can cover the weak Raman signals. Cleaning up the laser’s emission spectrum can be challenging especially for the low-frequency Raman range close to the excitation wavelength. During qualification, the laser revealed no detectable ASE. The figure shows a Raman spectrum of an L-Cystin sample recorded at excitation wavelengths of 455 nm and 520 nm.

“The integration of the C-WAVE with our TriVista system went smoothly. The user-friendly software and automatic tuning functionality made it easy to control the laser. It is impressive that its beam position and pointing is so stable even after tuning over a range of 200 nm across the visible spectrum. This fact in combination with the perfect Gaussian beam profile reduces the complexity of the optical setup and helps speed up experimental work,” says Jannick Saatz, R&D engineer at S&I. (Source: Hübner)