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Title: Photon entanglement entropy as a probe of many-body correlations and fluctuations
Recent theories and experiments have explored the use of entangled photons as a spectroscopic probe of physical systems. We describe here a theoretical description for entropy production in the scattering of an entangled biphoton Fock state within an optical cavity. We develop this using perturbation theory by expanding the biphoton scattering matrix in terms of single-photon terms in which we introduce the photon-photon interaction via a complex coupling constant, ξ. We show that the von Neumann entropy provides a concise measure of this interaction. We then develop a microscopic model and show that in the limit of fast fluctuations, the entanglement entropy vanishes, whereas in the limit of slow fluctuations, the entanglement entropy depends on the magnitude of the fluctuations and reaches a maximum. Our result suggests that experiments measuring biphoton entanglement give microscopic information pertaining to exciton-exciton correlations.  more » « less
Award ID(s):
1836075
NSF-PAR ID:
10098764
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
The Journal of chemical physics
Volume:
150
Issue:
18
ISSN:
0021-9606
Page Range / eLocation ID:
184106
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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