Nb-based Josephson parametric amplifier for superconducting qubit measurement

作     者：Fei-Fan Su Zi-Ting Wang Hui-Kai Xu Shou-Kuan Zhao Hai-Sheng Yan Zhao-Hua Yang Ye Tian Shi-Ping Zhao 宿非凡;王子婷;徐晖凯;赵寿宽;严海生;杨钊华;田野;赵士平

作者机构：Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of Sciences(CAS)Beijing 100190China School of Physical SciencesUniversity of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Topological Quantum ComputationUniversity of Chinese Academy of SciencesBeijing 100190China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2019年第28卷第11期

页      面：109-113页

核心收录：

学科分类：07[理学] 070201[理学-理论物理] 0702[理学-物理学] 

基　　金：Project supported by the Science Funds from the Ministry of Science and Technology of China(Grant Nos.2015CB921104 and 2016YFA0300601) the National Natural Science Foundation of China(Grant Nos.11674380 and 11874063) the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDB07010300 and XDB28000000) the Key Research and Development Program of Guangdong Province,China(Grant No.2018B030326001) 

主　　题：superconducting qubit Josephson parametric amplifier device fabrication quantum nondemolition measurement 

摘      要：We report a fabrication process and characterization of the Josephson parametric amplifier(JPA) for the single-shot quantum state measurement of superconducting multiqubit system. The device is prepared using Nb film as its base layer,which is convenient in the sample patterning process like e-beam lithography and film etching. Our results show that the JPA has a bandwidth up to 600 MHz with gain above 15 dB and noise temperature approaching the quantum limit. The qubit state differentiation measurements demonstrate the signal-to-noise ratio around 3 and the readout fidelity above 97%and 91% for the ground and first-excited states, respectively.