COvariance Based RAman Spectrometer (COBRAS)

ended

In COBRAS we will establish Femtosecond Covariance Spectroscopy, a new spectroscopic technique to measure the optical response of material which is based on stochastic light pulses characterized by frequency uncorrelated intensity fluctuation. By using light with different property every repetition, each reiteration of the experiment can be considered as a measurement under new conditions rather than a repetition of the same experiment. Crucially, within the ERC_StG project INCEPT we have demonstrated that in this limit the frequency of the Raman modes of a sample can be retrieved by measuring the spectral correlations in different pulses which are induced by the interaction with the sample. This is in striking contrast with standard approaches to Raman spectroscopy which are based on the measurement of the integrated emission of Raman sidebands at a given frequency and therefore require a high stability and low noise detection which can be reached only at a significant expense. Conversely, in covariance-based methods noise is a resource that can be exploited (rather than an impediment) and a much simpler and cheaper architecture for the spectrometer can be envisioned. The central idea of COBRAS is to set the way for commercial exploitation of covariance-based approaches to Raman spectroscopy. To this purpose we will develop a prototype spectrometer, study the general applicability of the covariance based methods and identify viable strategies for the commercialization of the spectrometer developed. We stress that the concept proposed here for Raman spectroscopy can be extended to different optical techniques and wavelength ranges. This make us confident that the COBRAS investment may represent a paradigmatic change in the approach to optical spectroscopy, potentially disclosing a new market across different industrial and scientific spectroscopic applications.