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Transient measurement of phononic states with covariance-based stochastic spectroscopy.

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.

SUBMITTER: Sparapassi G

PROVIDER: S-EPMC8885707 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Transient measurement of phononic states with covariance-based stochastic spectroscopy.

Sparapassi Giorgia G Cavaletto Stefano M SM Tollerud Jonathan J Montanaro Angela A Glerean Filippo F Marciniak Alexandre A Giusti Fancesca F Mukamel Shaul S Fausti Daniele D

Light, science & applications 20220301 1

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 ...[more]

PMID: 35228519

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