量子光学学报, 2019, 25 (2): 117, 网络出版: 2020-03-09
编码于单个中性原子的单量子比特的量子层析
Quantum Tomography of a Single Qubit Encoded in the Single Neutral Atom
密度矩阵 量子态层析 量子过程层析 最大似然估计法 density matrix quantum state tomography quantum process tomography maximum-likelihood estimation
摘要
量子态层析和量子过程层析是刻画量子态和量子操作过程准确度的基本工具。本文主要对编码于二能级铯原子的单量子比特及其单量子操作进行了相关实验研究,对编码在铯原子钟态的量子态(-i|0〉+|1〉)2进行了量子态层析分析,得到其保真度为097±002。我们还对单量子比特的门操作Rx(π)、Rxπ2、Ry(π)、Ryπ2、Rzπ2进行了量子过程层析测量,得到量子门操作的平均保真度为096±003。我们对影响单比特态及其操作过程的保真度的因素进行了分析。
Abstract
To characterize the accuracy of quantum state and quantum process,quantum state tomography and quantum process tomography as the basic tools,are developed.In our experiment,a single qubit is encoded in the cesium “clock states”.The fidelity of the prepared quantum state (-i|0〉+|1〉)2 is 097±002,which is characterized by the quantum state tomography.And we achieve an average fidelity of 096±003 of the quantum rotation gates Rx(π)、Rxπ2、Ry(π)、Ryπ2、Rzπ2 with the technique of quantum process tomography.The measures to further improve the fidelity is discussed.
田亚莉, 王志辉, 杨鹏飞, 张鹏飞, 李刚, 张天才. 编码于单个中性原子的单量子比特的量子层析[J]. 量子光学学报, 2019, 25(2): 117. TIAN Ya-li, WANG Zhi-hui, YANG Peng-fei, ZHANG Peng-fei, LI Gang, ZHANG Tian-cai. Quantum Tomography of a Single Qubit Encoded in the Single Neutral Atom[J]. Acta Sinica Quantum Optica, 2019, 25(2): 117.