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arXiv · 1807.00383

Polarization entanglement by time-reversed Hong-Ou-Mandel interference

Yuanyuan Chen·Sebastian Ecker·Sören Wengerowsky·Lukas Bulla·Siddarth Koduru Joshi·Fabian Steinlechner·Rupert Ursin
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Abstract

Sources of entanglement are an enabling resource in quantum technology, and pushing the limits of generation rate and quality of entanglement is a necessary pre-requisite towards practical applications. Here, we present an ultra-bright source of polarization-entangled photon pairs based on time-reversed Hong-Ou-Mandel interference. By superimposing four pair-creation possibilities on a polarization beam splitter, pairs of identical photons are separated into two spatial modes without the usual requirement for wavelength distinguishability or non-collinear emission angles. Our source yields high-fidelity polarization entanglement and high pair-generation rates without any requirement for active interferometric stabilization, which makes it an ideal candidate for a variety of applications, in particular those requiring indistinguishable photons.

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Yuanyuan Chen, Sebastian Ecker, Sören Wengerowsky, Lukas Bulla, Siddarth Koduru Joshi, Fabian Steinlechner, Rupert Ursin. 2019-08-01. Polarization entanglement by time-reversed Hong-Ou-Mandel interference. https://doi.org/10.1103/physrevlett.121.200502

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