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arXiv · 2009.06811

Phase Locking between Two All-Optical Quantum Memories

Fumiya Okamoto·Mamoru Endo·Mikihisa Matsuyama·Yuya Ishizuka·Yang Liu·Rei Sakakibara·Yosuke Hashimoto·Jun-ichi Yoshikawa·Peter van Loock·Akira Furusawa
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Abstract

Optical approaches to quantum computation require the creation of multi-mode photonic quantum states in a controlled fashion. Here we experimentally demonstrate phase locking of two all-optical quantum memories, based on a concatenated cavity system with phase reference beams, for the time-controlled release of two-mode entangled single-photon states. The release time for each mode can be independently determined. The generated states are characterized by two-mode optical homodyne tomography. Entanglement and nonclassicality are preserved for release-time differences up to 400 ns, confirmed by logarithmic negativities and Wigner-function negativities, respectively.

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Fumiya Okamoto, Mamoru Endo, Mikihisa Matsuyama, Yuya Ishizuka, Yang Liu, Rei Sakakibara, Yosuke Hashimoto, Jun-ichi Yoshikawa, Peter van Loock, Akira Furusawa. 2020-09-15. Phase Locking between Two All-Optical Quantum Memories. https://doi.org/10.1103/physrevlett.125.260508

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