Quantum gate identification: Error analysis, numerical results and optical experiment

Date

2019-03

Authors

Wang, Yuanlong
Yin, Qi
Dong, Daoyi
Qi, Bo
Petersen, Ian
Hou, Zhibo
Yonezawa, Hidehiro
Xiang, Guoyong

Journal Title

Journal ISSN

Volume Title

Publisher

Pergamon-Elsevier Ltd

Abstract

The identification of an unknown quantum gate is a significant issue in quantum technology. In this paper, we propose a quantum gate identification method within the framework of quantum process tomography. In this method, a series of pure states are applied to the gate and then a fast state tomography on the output states is performed and the data are used to reconstruct the quantum gate. The algorithm has computational complexity with the system dimension . The identification approach is compared with the maximum likelihood estimation method for the running time, which shows an efficiency advantage of our method. An error upper bound is established for the identification algorithm and the robustness of the algorithm against impurities in the input states is also tested. We perform a quantum optical experiment on a single-qubit Hadamard gate to verify the effectiveness of the identification algorithm.

Description

Keywords

Quantum system, Quantum tomography, Quantum gate identification, Computational complexity

Citation

Source

Automatica

Type

Journal article

Book Title

Entity type

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Restricted until

2037-12-31