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Mutual Cross Modulation of Two Laser Beams at the Individual-Photon Level



Michael Gullans, Kristin M. Beck, Qian Lin, M D. Lukin, Vladan Vuletic, Wenlan Chen


The realization of deterministic photon-photon interactions is a long-standing goal in optical science. Using an atomic ensemble inside a cavity, we demonstrate the mutual cross modulation of two continuous light beams at the level of individual photons. The originally uncorrelated beams derived from independent lasers become anticorrelated, as evidenced by an equal-time cross- correlation function g(2) = 0.89(1), showing that one photon in one beam extinguishes a photon in the other beam with a probability of 11%. Further technical improvements should enable the non-destructive continuous detection of traveling optical photons.
Physical Review Letters


quantum optics, cavity QED, single photon switch


Gullans, M. , Beck, K. , Lin, Q. , Lukin, M. , Vuletic, V. and Chen, W. (2014), Mutual Cross Modulation of Two Laser Beams at the Individual-Photon Level, Physical Review Letters, [online], (Accessed July 24, 2024)


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Created September 12, 2014, Updated November 10, 2018