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arXiv · 2009.07868

Fiber-compatible photonic feed-forward with 99% fidelity

G. L. Zanin·M. J. Jacquet·M. Spagnolo·P. Schiansky·I. Alonso Calafell·L. A. Rozema·P. Walther
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Abstract

Both photonic quantum computation and the establishment of a quantum internet require fiber-based measurement and feed-forward in order to be compatible with existing infrastructure. Here we present a fiber-compatible scheme for measurement and feed-forward, whose performance is benchmarked by carrying out remote preparation of single-photon polarization states at telecom-wavelengths. The result of a projective measurement on one photon deterministically controls the path a second photon takes with ultrafast optical switches. By placing well-calibrated {bulk} passive polarization optics in the paths, we achieve a measurement and feed-forward fidelity of (99.0 $\pm$ 1)%, after correcting for other experimental errors. Our methods are useful for photonic quantum experiments including computing, communication, and teleportation.

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G. L. Zanin, M. J. Jacquet, M. Spagnolo, P. Schiansky, I. Alonso Calafell, L. A. Rozema, P. Walther. 2020-09-16. Fiber-compatible photonic feed-forward with 99% fidelity. https://doi.org/10.1364/oe.409867

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