基于坐标系旋转实现对实数态克隆的优化

量子电子学报 ›› 2020, Vol. 37 ›› Issue (3): 337-341.

基于坐标系旋转实现对实数态克隆的优化

朱孟正1,2，赵春然2，公丕锋1,2，叶柳3

1 淮北师范大学信息学院,~~~安徽~~~淮北~~~235000;2 淮北师范大学物理与电子信息学院,~~~安徽~~~淮北~~~235000; 3 安徽大学物理与材料科学学院,~~~安徽~~~合肥~~~230039~

收稿日期:2019-09-20 修回日期:2019-10-23 出版日期:2020-05-28 发布日期:2020-05-28
通讯作者: 联系方式 E-mail:mzzhu@139.com
作者简介:朱孟正（1978—），安徽人，博士，副教授，主要从事量子信息方面的研究。Email: mzzhu@139.com
基金资助:
Supported by Natural Science Foundation of Anhui Province of China (安徽省自然科学基金，1808085MA08)，Natural Science Foundation of Anhui Higher Education Institutions of China (安徽省高等学校自然科学研究项目，KJ2018A0672；KJ2018A0679)

Optimizing real state cloning based on the rotation of coordinate system

ZHU Mengzheng1,2, ZHAO Chunran2, GONG Pifeng1,2, YE Liu3

1 Information College, Huaibei Normal University, Huaibei 235000, China; 2 School of Physics and Electronic Information, Huaibei Normal University, Huaibei 235000, China; 3 School of Physics and Material Science, Anhui University, Hefei 230039, China

Received:2019-09-20 Revised:2019-10-23 Published:2020-05-28 Online:2020-05-28

摘要/Abstract

摘要： 实数态克隆是量子克隆的一个重要组成部分。但要想直接根据保真度优化操作的方法来获得优化的非对称实数态克隆变换关系式，数学运算上非常繁琐，且得到的结果也不简洁明了。因此通过引入坐标系旋转变换的方法，原坐标系中的实数态克隆在新坐标系中就变成了相位协变克隆。基于表象变换知识，对照优化的非对称相位协变克隆，可实现非对称实数态克隆在原坐标系中的优化，即得到了优化的非对称实数态克隆变换的一组系数。采用此方法优化非对称实数态克隆，处理运算的思路清晰，优化结果对称、工整、简洁，并可明确地得到优化的非对称实数态克隆各不同系数之间满足的特定关系。

关键词: 量子信息, 量子克隆, 表象变换, 实数态克隆, 相位协变克隆

Abstract: Real state cloning is an important part of quantum cloning. However，for obtaining the optimal asymmetric real state cloning by using the method of optimizing the fidelity directly, the mathematical operation process is very cumbersome, and the results are not very simple and clear. For this reason, the method of coordinate system rotation transformation is introduced. Based on the transformation of coordinate system rotation, a real state cloning in the original coordinate system will become a well-known phase-covariant cloning in the new coordinate system. According to representation transformation, the optimization of asymmetric real state cloning can be realized easily in the original coordinate system by comparison with optimized asymmetric phase covariant cloning, that is, a set of coefficients for the optimized asymmetric real state clone transformation can be obtained. It is shown that using the method to optimize asymmetric real state cloning, the idea of processing operation is clear, and the optimization result is symmetrical, neat, and concise. In addition, the specific relationships between different coefficients of the optimized asymmetric real state clone can be obtained explicitly.

Key words: quantum information, quantum cloning, representation transformation, real state cloning, phase-covariant cloning

中图分类号:

O431.2

朱孟正, 赵春然, 公丕锋, 叶柳. 基于坐标系旋转实现对实数态克隆的优化[J]. 量子电子学报, 2020, 37(3): 337-341.

ZHU Mengzheng, ZHAO Chunran, GONG Pifeng, YE Liu. Optimizing real state cloning based on the rotation of coordinate system[J]. Chinese Journal of Quantum Electronics, 2020, 37(3): 337-341.

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