Nb-based Josephson parametric amplifier for superconducting qubit measurement<xref rid="cpb_28_11_110303fn1" ref-type="fn">*</xref><fn id="cpb_28_11_110303fn1"><label>*</label><p>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), and the Key Research and Development Program of Guangdong Province, China (Grant No. 2018B030326001).</p></fn>

Nb-based Josephson parametric amplifier for superconducting qubit measurement**

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), and the Key Research and Development Program of Guangdong Province, China (Grant No. 2018B030326001).

Su Fei-Fan^{1, 2}, Wang Zi-Ting^{1, 2}, Xu Hui-Kai^{1, 2}, Zhao Shou-Kuan^{1, 2}, Yan Hai-Sheng^{1, 2}, Yang Zhao-Hua^{1, 2}, Tian Ye^{1, 2}, Zhao Shi-Ping^{1, 2, 3, †}

Circuit diagram of the IMPA with its surrounding accessories. The circulator on the left is used to separate the incoming and amplified outgoing signals. There is a coaxial cable with length L connecting the circulator on one side and the IMPA via wire bonding on the other. On the right side of the IMPA there is a bias tee to combine the dc bias and rf pump for driving the IMPA.