An easily-prepared impedance matched Josephson parametric amplifier

• 作者: Ya-Peng Lu Quan Zuo Jia-Zheng Pan Jun-Liang Jiang Xing-Yu Wei Zi-Shuo Li Wen-Qu Xu Kai-Xuan Zhang Ting-Ting Guo Shuo Wang Chun-Hai Cao Wei-Wei Xu Guo-Zhu Sun Pei-Heng Wu
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（6）
• 所属期刊栏目: SPECIAL TOPIC—Quantum computation and quantum simulation
• 页码范围: 53-57
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/1674-1056/ac0420

摘要

An impedance matched parametric amplifier (IMPA) with Josephson junctions is fabricated and characterized.A hybrid structure containing coplanar and strip structures is implemented to realize an impedance taper line and a plate capacitor in an LC nonlinear resonator based on Josephson junctions.The upper plate of the capacitor is isolated with SiNx without grounding as well as the strips.Such easily-prepared designs greatly reduce the requirements for lithography alignment and precision,which makes the fabrication process more reliable.The experimental results show that in such IMPA a gain higher than 25 dB with a bandwidth of about 100 MHz can be obtained.This broadband amplifier operates close to the quantum limit.By adjusting the working point,a higher bandwidth of about 400 MHz can be obtained with a gain of about 17 dB.