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arXiv · 1808.07015

Hong-Ou-Mandel interference of polarization qubits stored in independent room-temperature quantum memories

Sonali Gera·Chase Wallace·Mael Flament·Alessia Scriminich·Mehdi Namazi·Youngshin Kim·Steven Sagona-Stophel·Giuseppe Vallone·Paolo Villoresi·Eden Figueroa
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Abstract

Quantum repeater networks require independent quantum memories capable of storing and retrieving indistinguishable photons to perform high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance to the realization of scalable quantum networks. We perform Hong-Ou-Mandel (HOM) interference between photonic polarization qubits stored and retrieved from two sets of independent room-temperature quantum memories. We show a steady improvement in memory parameters and visibilities, culminating in a high quantum memory HOM visibility of 43%, compared to the 48% no-memory limit of our set-up. These results lay the groundwork for future applications using large-scale memory-assisted quantum networks.

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Sonali Gera, Chase Wallace, Mael Flament, Alessia Scriminich, Mehdi Namazi, Youngshin Kim, Steven Sagona-Stophel, Giuseppe Vallone, Paolo Villoresi, Eden Figueroa. 2018-08-21. Hong-Ou-Mandel interference of polarization qubits stored in independent room-temperature quantum memories. https://doi.org/10.1038/s41534-024-00803-2

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