This paper demonstrates the use of entangled photons in femtosecond time-resolved coherent Raman spectroscopy to monitor electronic and vibrational coherences, leading to a novel technique called Quantum Femtosecond Raman Spectroscopy (QFRS). The authors present a scheme using photon entanglement and nonlinear interferometry, distinct from classical CARS and FSRS. They show improved time-frequency resolution through explicit results for a quantum extension of FAST CARS, examining both intensity-correlated and heterodyne-detected QFRS signals.

Zhang