Saved in:
Bibliographic Details
Main Authors: Gao, Ran, Wu, Feng, Sun, Hantao, Chen, Jianjun, Deng, Hao, Ma, Xizheng, Miao, Xiaohe, Song, Zhijun, Wan, Xin, Wang, Fei, Xia, Tian, Ying, Make, Zhang, Chao, Shi, Yaoyun, Zhao, Hui-Hai, Deng, Chunqing
Format: Preprint
Published: 2023
Subjects:
Online Access:https://arxiv.org/abs/2310.06621
Tags: Add Tag
No Tags, Be the first to tag this record!
Table of Contents:
  • Introducing disorderness in the superconducting materials has been considered promising to enhance the electromagnetic impedance and realize noise-resilient superconducting qubits. Despite a number of pioneering implementations, the understanding of the correlation between the material disorderness and the qubit coherence is still developing. Here, we demonstrate a systematic characterization of fluxonium qubits with the superinductors made from titanium-aluminum-nitride with varied disorderness. From qubit noise spectroscopy, the flux noise and the dielectric loss are extracted as a measure of the coherence properties. Our results reveal that the $1/f$ flux noise dominates the qubit decoherence around the flux-frustration point, strongly correlated with the material disorderness; while the dielectric loss remains low under a wide range of material properties. From the flux-noise amplitudes, the areal density ($σ$) of the phenomenological spin defects and material disorderness are found to be approximately correlated by $σ\propto ρ_{xx}^3$, or effectively $(k_F l)^{-3}$. This work has provided new insights on the origin of decoherence channels within superconductors, and could serve as a useful guideline for material design and optimization.