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Title: 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.  more » « less
Award ID(s):
1953045
PAR ID:
10340548
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Light: Science & Applications
Volume:
11
Issue:
1
ISSN:
2047-7538
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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