The noise-biased Kerr-cat qubit is an attractive candidate for fault-tolerant quantum computation; however, its initialization faces challenges due to the squeezing pump-induced frequency shift (PIFS). Here, we propose and demonstrate a dynamic compensation method to mitigate the effect of PIFS during the Kerr-cat qubit initialization. Utilizing a novel nonlinearity-engineered triple-loop SQUID device, we realize a stabilized Kerr-cat qubit and validate the advantages of the dynamic compensation method by improving the initialization fidelity from 57% to 78%, with a projected fidelity of 91% after excluding state preparation and measurement errors. Our results not only advance the practical implementation of Kerr-cat qubits, but also provide valuable insights into the fundamental adiabatic dynamics of these systems. This work paves the way for scalable quantum processors that leverage the bias-preserving properties of Kerr-cat qubits.
Cite
@article{arxiv.2408.14112,
title = {Dynamic compensation for pump-induced frequency shift in Kerr-cat qubit initialization},
author = {Yifang Xu and Ziyue Hua and Weiting Wang and Yuwei Ma and Ming Li and Jiajun Chen and Jie Zhou and Xiaoxuan Pan and Lintao Xiao and Hongwei Huang and Weizhou Cai and Hao Ai and Yu-xi Liu and Chang-Ling Zou and Luyan Sun},
journal= {arXiv preprint arXiv:2408.14112},
year = {2025}
}