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arXiv quant-ph/04100222004-10quant-ph

Production of superpositions of coherent states in traveling optical fields with inefficient photon detection

H. Jeong, A. P. Lund, T. C. Ralph

备注：: 13 pages, 9 figures, to be published in Phys. Rev. A
发表信息：: Phys. Rev. A 72, 013801 (2005)
DOI：: 10.1103/PhysRevA.72.013801

英文摘要：

We develop an all-optical scheme to generate superpositions of macroscopically distinguishable coherent states in traveling optical fields. It non-deterministically distills coherent state superpositions (CSSs) with large amplitudes out of CSSs with small amplitudes using inefficient photon detection. The small CSSs required to produce CSSs with larger amplitudes are extremely well approximated by squeezed single photons. We discuss some remarkable features of this scheme: it effectively purifies mixed initial states emitted from inefficient single photon sources and boosts negativity of Wigner functions of quantum states.

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