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arXiv · 1806.01245

THz-bandwidth all-optical switching of heralded single photons

Connor Kupchak·Jennifer Erskine·Duncan G. England·Benjamin J. Sussman
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Abstract

Optically induced ultrafast switching of single photons is demonstrated by rotating the photon polarization via the Kerr effect in a commercially available single mode fiber. A switching efficiency of 97\% is achieved with a $\sim1.7$\,ps switching time, and signal-to-noise ratio of $\sim800$. Preservation of the quantum state is confirmed by measuring no significant increase in the second-order autocorrelation function $g^{(2)}(0)$. These values are attained with only nanojoule level pump energies that are produced by a laser oscillator with 80\,MHz repetition rate. The results highlight a simple switching device capable of both high-bandwidth operations and preservation of single-photon properties for applications in photonic quantum processing and ultrafast time-gating or switching.

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Connor Kupchak, Jennifer Erskine, Duncan G. England, Benjamin J. Sussman. 2018-06-12. THz-bandwidth all-optical switching of heralded single photons. https://doi.org/10.1364/ol.44.001427

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