High-rate multiplexed entanglement source based on time-bin qubits for advanced quantum networks

Andrew Mueller; Samantha Davis; Boris Korzh; Raju Valivarthi; Andrew D. Beyer; Rahaf Youssef; Neil Sinclair; Cristián Peña; Matthew D. Shaw; Maria Spiropulu

arXiv · 2310.01804

High-rate multiplexed entanglement source based on time-bin qubits for advanced quantum networks

Andrew Mueller·Samantha Davis·Boris Korzh·Raju Valivarthi·Andrew D. Beyer·Rahaf Youssef·Neil Sinclair·Cristián Peña·Matthew D. Shaw·Maria Spiropulu

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Abstract

Entanglement distribution based on time-bin qubits is an attractive option for emerging quantum networks. We demonstrate a 4.09 GHz repetition rate source of photon pairs entangled across early and late time bins separated by 80 ps. Simultaneous high rates and high visibilities are achieved through frequency multiplexing the spontaneous parametric down conversion output into 8 time-bin entangled pairs. We demonstrate entanglement visibilities as high as 99.4%, total entanglement rates up to 3.55e6 coincidences/s, and predict a straightforward path towards achieving up to an order of magnitude improvement in rates without compromising visibility. Finally, we resolve the density matrices of the entangled states for each multiplexed channel and express distillable entanglement rates in ebit/s, thereby quantifying the tradeoff between visibility and coincidence rates that contributes to useful entanglement distribution. This source is a fundamental building block for high-rate entanglement-based quantum key distribution systems or advanced quantum networks.

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Andrew Mueller, Samantha Davis, Boris Korzh, Raju Valivarthi, Andrew D. Beyer, Rahaf Youssef, Neil Sinclair, Cristián Peña, Matthew D. Shaw, Maria Spiropulu. 2023-10-03. High-rate multiplexed entanglement source based on time-bin qubits for advanced quantum networks. https://arxiv.org/abs/2310.01804

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