Chin. Phys. Lett.  2004, Vol. 21 Issue (10): 1877-1880    DOI:
Original Articles |
Squeezing and Entanglement in Continuous Variable Systems
XIA Yun-Jie1,2;GUO Guang-Can1
1Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026 2Department of Physics, Qufu Normal University, Qufu, 273165
Cite this article:   
XIA Yun-Jie, GUO Guang-Can 2004 Chin. Phys. Lett. 21 1877-1880
Download: PDF(207KB)  
Export: BibTeX | EndNote | Reference Manager | ProCite | RefWorks
Abstract Based on total variance of a pair of Einstein-Podolsky-Rosen (EPR) type operators, the generalized EPR entangled states in continuous variable systems are defined. We show that such entangled states must correspond to two-mode squeezing states whether these states are Gaussian or not and whether they are pure or not. With help of the relation between the total variance and the entanglement, the degree of such entanglement is also defined. Through analysing some specific cases, we see that this method is very convenient and easy in practical applications. In addition, an entangled state with no squeezing is studied, which reveals that there certainly exists something unknown about entanglement in continuous variable systems.


Keywords: 03.65.Ud      42.50.Dv     
Published: 01 October 2004
PACS:  03.65.Ud (Entanglement and quantum nonlocality)  
  42.50.Dv (Quantum state engineering and measurements)  
TRENDMD:   
URL:  
https://cpl.iphy.ac.cn/       OR      https://cpl.iphy.ac.cn/Y2004/V21/I10/01877
Service
E-mail this article
E-mail Alert
RSS
Articles by authors
XIA Yun-Jie
GUO Guang-Can
Related articles from Frontiers Journals
[1] GUO Yu, LUO Xiao-Bing. Quantum Teleportation between Two Distant Bose–Einstein Condensates[J]. Chin. Phys. Lett., 2012, 29(6): 1877-1880
[2] REN Jie, WU Yin-Zhong, ZHU Shi-Qun. Quantum Discord and Entanglement in Heisenberg XXZ Spin Chain after Quenches[J]. Chin. Phys. Lett., 2012, 29(6): 1877-1880
[3] SHAN Chuan-Jia,**,CAO Shuai,XUE Zheng-Yuan,ZHU Shi-Liang. Anomalous Temperature Effects of the Entanglement of Two Coupled Qubits in Independent Environments[J]. Chin. Phys. Lett., 2012, 29(4): 1877-1880
[4] CHEN Peng,QIAN Jun,CHEN Dong-Yuan,HU Zheng-Feng**,WANG Yu-Zhu**. Interference of a Narrowband Biphoton with Double Electromagnetically Induced Transparency in an N-Type System[J]. Chin. Phys. Lett., 2012, 29(4): 1877-1880
[5] GAO Gui-Long,SONG Fu-Quan,HUANG Shou-Sheng,WANG Yan-Wei,FAN Zhi-Qiang,YUAN Xian-Zhang,JIANG Nian-Quan**. Producing and Distinguishing χ-Type Four-Qubit States in Flux Qubits[J]. Chin. Phys. Lett., 2012, 29(4): 1877-1880
[6] LI Hong-Rong**,ZHANG Pei,GAO Hong,BI Wen-Ting,ALAMRI M. D.,LI Fu-Li. Non-Equilibrium Quantum Entanglement in Biological Systems[J]. Chin. Phys. Lett., 2012, 29(4): 1877-1880
[7] GE Rong-Chun, LI Chuan-Feng, GUO Guang-Can. Spin Dynamics in the XY Model[J]. Chin. Phys. Lett., 2012, 29(3): 1877-1880
[8] CAO Ming-Tao, HAN Liang, QI Yue-Rong, ZHANG Shou-Gang, GAO Hong, LI Fu-Li. Calculation of the Spin-Dependent Optical Lattice in Rubidium Bose–Einstein Condensation[J]. Chin. Phys. Lett., 2012, 29(3): 1877-1880
[9] M. Ramzan. Decoherence and Multipartite Entanglement of Non-Inertial Observers[J]. Chin. Phys. Lett., 2012, 29(2): 1877-1880
[10] Piotr Zawadzki**. New View of Ping-Pong Protocol Security[J]. Chin. Phys. Lett., 2012, 29(1): 1877-1880
[11] LI Jun-Gang, **, ZOU Jian, **, XU Bao-Ming, SHAO Bin, . Quantum Correlation Generation in a Damped Cavity[J]. Chin. Phys. Lett., 2011, 28(9): 1877-1880
[12] ZHANG Ai-Ping**, QIANG Wen-Chao, LING Ya-Wen, XIN Hong, YANG Yong-Ming . Geometric Phase for a Qutrit-Qubit Mixed-Spin System[J]. Chin. Phys. Lett., 2011, 28(8): 1877-1880
[13] ZHENG An-Shou, **, LIU Ji-Bing, CHEN Hong-Yun . N−Qubit W State of Spatially Separated Atoms via Fractional Adiabatic Passage[J]. Chin. Phys. Lett., 2011, 28(8): 1877-1880
[14] FANG Bin, LIU Bi-Heng, HUANG Yun-Feng**, SHI Bao-Sen, GUO Guang-Can . Spectrum Analysis of a Pulsed Photon Source Generated from Periodically Poled Lithium Niobate[J]. Chin. Phys. Lett., 2011, 28(7): 1877-1880
[15] CHEN Peng, ZHOU Shu-Yu, XU Zhen, DUAN Ya-Fan, CUI Guo-Dong, HONG Tao, WANG Yu-Zhu** . Narrowband Biphoton Generation with Four-Wave Mixing in a Far-Detuning Three-Level System[J]. Chin. Phys. Lett., 2011, 28(7): 1877-1880
Viewed
Full text


Abstract