连续变量系统中的纠缠与非定域性

J4 ›› 2017, Vol. 34 ›› Issue (1): 62-71.

连续变量系统中的纠缠与非定域性

廖长庚¹,郑小兰²,胡淳³,何志敏¹,陈开洪¹

1福建信息职业技术学院光电器件集成工程中心，福建福州 350003； 2福建工程学院国脉信息学院, 福建福州 350014； 3龙岩学院物理系, 福建龙岩 364012

收稿日期:2015-07-15 修回日期:2015-11-24 出版日期:2017-01-28 发布日期:2017-01-28
通讯作者: 廖长庚（1985-）硕士，助教，主要从事量子光学与量子信息方面的研究。 E-mail:liaochanggeng@hotmail.com
基金资助:
Supported by Research Foundation of Education Bureau of Fujian Province(福建省教育厅A类科技项目，JA14379 )

Entanglement and nonlocality in continuous variable systems

LIAO Changgeng1, ZHENG Xiaolan2, HU Chun3, HE Zhimin1, CHEN Kaihong1

1 Center of Optoelectronic Device Integration Engineering, FuJian Polytechnic of Information Technology, Fuzhou 350003, China； 2 Guomai Information College, Fujian University of Technology, Fuzhou 350014, China； 3 Department of Physics, Longyan University, Longyan 364012, China

Received:2015-07-15 Revised:2015-11-24 Published:2017-01-28 Online:2017-01-28

摘要/Abstract

摘要： 通过场（原子）约化熵、量子相对熵研究了各种双模非经典光场（包括纠缠相干态、对相干态、双模压缩真空态）与型三能级原子作用时的纠缠特性，讨论了原子初态和光场参数的影响，并与赝自旋算符构造的贝尔算符期待值进行了对比。结果表明：熵与贝尔算符期待值具有相似的演化趋势；相对于贝尔算符期待值,熵更易受原子相干性的影响；纠缠最大时非定域性也最大,纠缠最小时贝尔算符期待值并不是最小。在贝尔算符期待值较小时纠缠仍可能较大,这说明纠缠和非定域是量子世界中既相互关联又独立的2个不同属性。

关键词: 量子光学；熵特性；非定域性；双模相干光场；非简并双光子

Abstract: By using the field (atom) reduced entropy and quantum relative entropy, the entanglement properties of various two-mode non-classical optical fields(including the entangled coherent state, pair coherent state and two-mode squeezed vacuum state) interacting with a type three-level atom are investigated. Influences of the atom initial states and field parameters are discussed, and the comparison with Bell operator expectation value constructed by the pseudo spin operator is carried out. Results show that there is similar evolution trend between entropy and Bell operator expectation value. Compared with Bell operator expectation value, entropy is more easily influenced by atom coherence. The nonlocality is maximal when entanglement is maximal, and the expectation value of Bell operator is not the least when entanglement is minimal. When the expectation value of Bell operator is less, entanglement is still maybe larger. It shows that the entanglement and nonlocality are two kinds of interconnected and independent properties in the quantum world.

Key words: quantum optics; entropy properties; nonlocality; two-mode coherent optical field; non-degenerate two-photon Jaynes-Cummings model

中图分类号:

0413

廖长庚郑小兰胡淳何志敏陈开洪. 连续变量系统中的纠缠与非定域性[J]. J4, 2017, 34(1): 62-71.

LIAO Changgeng1, ZHENG Xiaolan2, HU Chun3, HE Zhimin1, CHEN Kaihong1. Entanglement and nonlocality in continuous variable systems[J]. J4, 2017, 34(1): 62-71.

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