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arXiv · 1501.00898

Two-Color Photon Correlations of the Light Scattered by a Quantum Dot

M. Peiris·B. Petrak·K. Konthasinghe·Y. Yu·Z. C. Niu·A. Muller
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Abstract

Two-color second-order correlations of the light scattered near-resonantly by a quantum dot were measured by means of spectrally-filtered coincidence detection. The effects of filter frequency and bandwidth were studied under monochromatic laser excitation, and a complete two-photon spectrum was reconstructed. In contrast to the ordinary one-photon spectrum, the two-photon spectrum is asymmetric with laser detuning and exhibits a rich structure associated with both real and virtual two-photon transitions down the "dressed states" ladder. Photon pairs generated via virtual transitions are found to violate the Cauchy-Schwartz inequality by a factor of 60. Our experiments are well described by the theoretical expressions obtained by del Valle et al. via time-and normally-ordered correlation functions.

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M. Peiris, B. Petrak, K. Konthasinghe, Y. Yu, Z. C. Niu, A. Muller. 2015-01-05. Two-Color Photon Correlations of the Light Scattered by a Quantum Dot. https://doi.org/10.1103/physrevb.91.195125

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