2007/03/16 by Hiroyuki Yamada, Katsuji Yamamoto
Computer Science · Physics and Astronomy · #Atomic physics #Cavity quantum electrodynamics #Cold Atom Physics and Bose-Einstein Condensates #Coupling (piping) #Materials science #Open quantum system #Photon #Physics #Quantum #Quantum Information and Cryptography #Quantum mechanics #Quantum optics #Quantum optics and atomic interactions #Qubit #quant-ph
paper · pdf · doi:10.1016/j.optcom.2007.02.046
18 pages, 4 figures, an extended version of quant-ph/0506215, to be published in Optics Communications
arxiv created 2007/03/16 · openalex publication_date 2007/03/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate a scheme of atomic quantum memory to store photonic qubits of polarization in cavity QED. It is observed that the quantum-state swapping between a single-photon pulse and a Λ-type atom can be made via scattering in an optical cavity [T. W. Chen, C. K. Law, P. T. Leung, Phys. Rev. A \bf 69 (2004) 063810]. This swapping operates limitedly in the strong coupling regime for Λ-type atoms with equal dipole couplings. We extend this scheme in cavity QED to present a more feasible and efficient method for quantum memory combined with projective measurement. This method works without requiring such a condition on the dipole couplings. The fidelity is significantly higher than that of the swapping, and even in the moderate coupling regime it reaches almost unity by narrowing sufficiently the photon-pulse spectrum. This high performance is rather unaffected by the atomic loss, cavity leakage or detunings, while a trade-off is paid in the success probability for projective measurement.