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arXiv · 2505.10638

Fiber-coupled broadband quantum memory for polarization-encoded photonic qubits

Sandra Cheng·Carson Evans·Todd Pittman
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Abstract

Various near-term quantum networking applications will benefit from low-loss, fiber-coupled photonic quantum memory devices with high efficiencies. We demonstrate a fiber-coupled loop-and-switch quantum memory platform with a pass-through efficiency of ~54% and an overall storage efficiency that scales as ~0.5^(N+1) where N is the number of storage cycles. We highlight the trade-off between memory lifetime and qubit accessibility in this platform by using two different storage cycle times of ~40 nanoseconds and ~0.5 microseconds, and demonstrate high-fidelity storage and retrieval of ultra-broadband single-photon polarization qubits in both cases.

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Sandra Cheng, Carson Evans, Todd Pittman. 2025-05-15. Fiber-coupled broadband quantum memory for polarization-encoded photonic qubits. https://doi.org/10.1038/s41534-025-01109-7

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