Traveling-wave parametric amplifiere-induced qubit dephasing:analysis and mitigation  

作　　者：Yingshan Zhang Huikai Xu Yu Song Yuqun Xu Shuang Yang Ziyue Hua Shoukuan Zhao Weiyang Liu Guangming Xue Yirong Jin Haifeng Yu 

机构地区：[1]Beijing Academy of Quantum Information Sciences,Beijing 100193,China [2]Center for Quantum Information,Institute for Interdisciplinary Information Sciences,Tsinghua University,Beijing 100084,China [3]Hefei National Laboratory,Hefei 230088,China

出　　处：《Chip》2023年第4期97-104,共8页芯片（英文）

基　　金：supported by the National Natural Science Foundation of China(NSFC-11890704);the Natural Science Foundation of Beijing(NSFB-Z190012);the Key-Area Research and Development Program of Guangdong Province(Grant No.2018B030326001).

摘　　要：The mitigation of dephasing poses a significant challenge toimproving the performance of error-prone superconducting quantum computing systems.Here,the dephasing of a transmon qubit ina dispersive readout regime was investigated by adopting aJosephson traveling-wave parametric amplifier as the preamplifier.Our findings reveal that the potent pump leakage from the preamplifier may lead to severe dephasing.This could be attributed to amixture of measurement-induced dephasing,ac Stark effect,andheating.It is showed that pulse-mode readout is a promising measurement scheme to mitigate qubit dephasing while minimizing theneed for bulky circulators.Our work provides key insights intomitigating decoherence from microwave-pumped preamplifiers,which will be critical for advancing large-scale quantum computers.

关 键 词：TWPA Microwave pump DEPHASING Pulse mode 

分 类 号：TP383[自动化与计算机技术—计算机系统结构]