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 ± 1)%, after correcting for other experimental errors. Our methods are useful for photonic quantum experiments including computing, communication, and teleportation.
@article{arxiv.2009.07868,
title = {Fiber-compatible photonic feed-forward with 99% fidelity},
author = {G. L. Zanin and M. J. Jacquet and M. Spagnolo and P. Schiansky and I. Alonso Calafell and L. A. Rozema and P. Walther},
journal= {arXiv preprint arXiv:2009.07868},
year = {2021}
}