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arXiv · 2111.14488

Transient measurement of phononic states with covariance-based stochastic spectroscopy

G. Sparapassi·S. M. Cavaletto·J. Tollerud·A. Montanaro·F. Glerean·A. Marciniak·F. Giusti·S. Mukamel·D. Fausti
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Abstract

We present a novel approach to transient Raman spectroscopy, which combines stochastic probe pulses and a covariance-based detection to measure stimulated Raman signals in alpha-quartz. A coherent broadband pump is used to simultaneously impulsively excite a range of different phonon modes, and the phase, amplitude, and energy of each mode are independently recovered as a function of the pump-probe delay by a noisy-probe and covariance-based analysis. Our experimental results and the associated theoretical description demonstrate the feasibility of 2D-Raman experiments based on the stochastic probe schemes, with new capabilities not available in equivalent mean-value-based 2D-Raman techniques. This work unlocks the gate for nonlinear spectroscopies to capitalize on the information hidden within the noise and overlooked by a mean-value analysis.

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G. Sparapassi, S. M. Cavaletto, J. Tollerud, A. Montanaro, F. Glerean, A. Marciniak, F. Giusti, S. Mukamel, D. Fausti. 2021-11-29. Transient measurement of phononic states with covariance-based stochastic spectroscopy. https://arxiv.org/abs/2111.14488

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