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Atomic Quantum Memory for Photonic Qubits via Scattering in Cavity QED

Hiroyuki Yamada·Katsuji Yamamoto
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Abstract

We investigate a scheme of atomic quantum memory to store photonic qubits in cavity QED. This is motivated on the recent observation that the quantum-state swapping between a single-photon pulse and a Lambda-type atom trapped in a cavity is ideally realized via scattering for some specific case in the strong coupling cavity regime [T. W. Chen, C. K. Law, and P. T. Leung, Phys. Rev. A 69, 063810 (2004)]. We derive a simple formula for calculating the fidelity of this atom-photon swapping for quantum memory. We further propose a feasible method which implements conditionally the quantum memory operation with the fidelity of almost unity even if the atom-photon coupling is not so strong. This method can also be applied to store a photonic entanglement in spatially separated atomic quantum memories.

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Hiroyuki Yamada, Katsuji Yamamoto. 2005-06-26. Atomic Quantum Memory for Photonic Qubits via Scattering in Cavity QED. https://arxiv.org/abs/quant-ph/0506215

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