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DOE OSTI · 1997560

Emulating Quantum Entangled Biphoton Spectroscopy Using Classical Light Pulses

Ko, Liwen·Cook, Robert L.·Whaley, K. Birgitta
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Abstract

We show that for a class of quantum light spectroscopy (QLS) experiments using n = 0, 1, 2, ··· classical light pulses and an entangled photon pair (a biphoton state) where one photon acts as a reference without interacting with the matter sample, identical signals can be obtained by replacing the biphotons with classical-like coherent states of light, where these are defined explicitly in terms of the parameters of the biphoton states. An input-output formulation of quantum nonlinear spectroscopy is used to prove this equivalence. We demonstrate the equivalence numerically by comparing a classical pump–quantum probe experiment with the corresponding classical pump–classical probe experiment. This analysis shows that understanding the equivalence between entangled biphoton probes and carefully designed classical-like coherent state probes leads to quantum-inspired classical experiments that yield equivalent signals and provides insights for the future design of QLS experiments that could provide a true quantum advantage.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYLightMathematical methodsMoleculesProbesSpectroscopylightmathematical methodsmoleculesprobesspectroscopy

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Ko, Liwen, Cook, Robert L., Whaley, K. Birgitta. 2023-08-31. Emulating Quantum Entangled Biphoton Spectroscopy Using Classical Light Pulses. https://doi.org/10.1021/acs.jpclett.3c01714

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