Effective squeezing enhancement via measurement-induced non-Gaussian operation and its application to the dense coding scheme

作     者：Akira Kitagawa Masahiro Takeoka Kentaro Wakui Masahide Sasaki 

作者机构：National Institute of Information and Communications Technology 4-2-1 Nukui-Kita Koganei Tokyo 184-8795 Japan Core Research for Evolutional Science and Technology Japan Science and Technology Agency 1-9-9 Yaesu Chuoh Tokyo 103-0028 Japan Department of Applied Physics The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-8656 Japan 

出 版 物：《Physical Review A》 (物理学评论A辑：原子、分子和光学物理学)

年 卷 期：2005年第72卷第2期

页      面：022334-022334页

核心收录：

学科分类：070207[理学-光学] 07[理学] 08[工学] 0803[工学-光学工程] 0702[理学-物理学] 

主　　题：STATES 

摘      要：We study the measurement-induced non-Gaussian operation on the single- and two-mode Gaussian squeezed vacuum states with beam splitters and on-off type photon detectors, with which mixed non-Gaussian states are generally obtained in the conditional process. It is known that the entanglement can be enhanced via this non-Gaussian operation on the two-mode squeezed vacuum state. We show that, in the range of practical squeezing parameters, the conditional outputs are still close to Gaussian states, but their second order variances of quantum fluctuations and correlations are effectively suppressed and enhanced, respectively. To investigate an operational meaning of these states, especially entangled states, we also evaluate the quantum dense coding scheme from the viewpoint of the mutual information, and we show that non-Gaussian entangled state can be advantageous compared with the original two-mode squeezed state.