Flux Crosstalk Calibration from Zero Knowledge to High Precision in Fully Tunable Superconducting Circuits
Abstract
Precise and independent flux control is essential for scalable superconducting processors built from frequency-tunable qubits and couplers, but flux crosstalk undermines it. Conventional calibration methods rely either on dedicated readout channels, which tunable couplers typically lack, or on readout schemes requiring extensive prior spectroscopy of the qubit and coupler. We demonstrate two independent methods that characterize coupler flux crosstalk without directly driving or measuring the couplers. The first method is zero-knowledge characterization, which exploits intrinsic coupler-resonator coupling to yield rapid and accurate estimates with no prior qubit or coupler spectroscopy, accelerating large scale bring-up. The second method is symmetric branch cancellation, which isolates crosstalk from other dispersive effects allowing for quantifying with high precision. Combined with an improved iterative procedure, these methods suppress residual coupler crosstalk below 5×10−5, providing a complete route from zero-knowledge initialization to high-precision crosstalk characterization in fully tunable architectures.
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BibTeX
@misc{gao2026flux,
title = {{Flux Crosstalk Calibration from Zero Knowledge to High Precision in Fully Tunable Superconducting Circuits}},
author = {Y. Gao and A. Galicia and J. R. Guimarães and Y. Haddad and Y. Liu and J. Cereijo and D. A. Volkov and H. Bhardwaj and M. Neis and M. Jerger and P. A. Bushev and R. Barends},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.06656},
eprint = {2611.06656},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.06656},
}
RIS
TY - UNPB
TI - Flux Crosstalk Calibration from Zero Knowledge to High Precision in Fully Tunable Superconducting Circuits
AU - Y. Gao
AU - A. Galicia
AU - J. R. Guimarães
AU - Y. Haddad
AU - Y. Liu
AU - J. Cereijo
AU - D. A. Volkov
AU - H. Bhardwaj
AU - M. Neis
AU - M. Jerger
AU - P. A. Bushev
AU - R. Barends
PY - 2026
DA - 2026/11/04
PB - arXiv
DO - 10.48550/arxiv.2611.06656
UR - https://arxiv.org/abs/2611.06656
AB - Precise and independent flux control is essential for scalable superconducting processors built from frequency-tunable qubits and couplers, but flux crosstalk undermines it. Conventional calibration methods rely either on dedicated readout channels, which tunable couplers typically lack, or on readout schemes requiring extensive prior spectroscopy of the qubit and coupler. We demonstrate two independent methods that characterize coupler flux crosstalk without directly driving or measuring the couplers. The first method is zero-knowledge characterization, which exploits intrinsic coupler-resonator coupling to yield rapid and accurate estimates with no prior qubit or coupler spectroscopy, accelerating large scale bring-up. The second method is symmetric branch cancellation, which isolates crosstalk from other dispersive effects allowing for quantifying with high precision. Combined with an improved iterative procedure, these methods suppress residual coupler crosstalk below 5×10^−5, providing a complete route from zero-knowledge initialization to high-precision crosstalk characterization in fully tunable architectures.
ER -