Fock空间中基于波色双模指数二次型算符的连续变量纠缠态的量子涨落特性

J4 ›› 2010, Vol. 27 ›› Issue (1): 31-39.

Fock空间中基于波色双模指数二次型算符的连续变量纠缠态的量子涨落特性

路俊哲^1,2 李安康¹ 马雷¹

1 上海华东师范大学物理系，上海 200062 ； 2 新疆师范大学物理系，新疆乌鲁木齐 830054

出版日期:2010-01-28 发布日期:2009-12-30
通讯作者: 马雷（1965-），男，上海华东师范大学物理系副教授，硕士生导师，主要研究领域为量子信息和量子计算. E-mail:lma@phy.ecnu.edu.cn
作者简介:路俊哲（1979-），女，华东师范大学物理系在读硕士研究生, 新疆师范大学物理系讲师，主要研究方向领域为量子信息和量子计算.E-mail: jz_lu@163.com

Quantum fluctuation properties of continuous-variable entangled state based on general two-mode Boson exponential quadratic operator in Fock space

LU Jun-Zhe^1,2, LI An-Kang¹, MA Lei¹

1 Department of Physics, East China Normal University, Shanghai 200062, China；
2 Department of Physics, Xinjiang Normal University, Urumchi 830054, China

Published:2010-01-28 Online:2009-12-30
Supported by:
National Fundamental Research Program Under Grant No. 2006CB921104 and National Natural Science Foundation of China under Grant No. 60708003

摘要/Abstract

摘要：

利用线性量子变换理论（LQTT），导出在Fock空间中连续变量两体纠缠态的量子涨落计算的一般公式，并讨论此纠缠态的压缩特性。通过线性拟合的方法，得到当涨落度和纠缠熵分别出现极值时，态参数之间关系。结果显示当达到较大纠缠时，该态的压缩程度也较大，除此以外还得到了涨落度随参数和纠缠熵的变化关系。同时举例说明此公式在计算双模压缩真空态和单边双模压缩真空态的量子涨落中的应用。

关键词: 量子光学, 量子涨落, 线性量子变换理论, 压缩特性, 连续变量纠缠态

Abstract:

By virtue of the linear quantum transformation theory(LQTT), a general formula was obtained, which calculate the quantum fluctuations for bipartite entangled state of continuous variables in Fock space. Moreover, the squeezed properties of the entangled state are discussed. The relations between the state parameters are depicted by means of the linear fit, when the degree of the fluctuation and entanglement entropy reach the extremum. When the entangled state is maximally entangled, the results show that the squeezed degree is also maximal. In addition, the changing relationship between the quantum fluctuations and the quantum entanglement is acquired. The derived formula are used to calculate the fluctuation of the common two-mode squeezed vacuum state and the two-mode one-sided squeezed vacuum state as examples.

Key words: quantum optics, quantum fluctuation, linear quantum transformation theory, squeezed properties, continuous-variable entangled states

路俊哲李安康马雷 . Fock空间中基于波色双模指数二次型算符的连续变量纠缠态的量子涨落特性[J]. J4, 2010, 27(1): 31-39.

LU Jun-Zhe, LI An-Kang, MA Lei. Quantum fluctuation properties of continuous-variable entangled state based on general two-mode Boson exponential quadratic operator in Fock space[J]. J4, 2010, 27(1): 31-39.

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