Characterization and Optimization of Tunable Couplers via Adiabatic Control in Superconducting Circuits

• URL: http://arxiv.org/abs/2501.13646v1
• Date: Thu, 23 Jan 2025 13:25:55 GMT
• Title: Characterization and Optimization of Tunable Couplers via Adiabatic Control in Superconducting Circuits
• Authors: Xuan Zhang, Xu Zhang, Changling Chen, Kai Tang, Kangyuan Yi, Kai Luo, Zheshu Xie, Yuanzhen Chen, Tongxing Yan,
• Abstract summary: We develop a hardware-efficient and robust technique based on adiabatic control to address the above issue.<n>We have characterized and calibrated tunable couplers in our chips.<n>We have also expanded this technique to tune the dispersive shift between a frequency-fixed qubit and its readout resonator over a wide range.
• Score: 8.141331634976625
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: In the pursuit of scalable superconducting quantum computing, tunable couplers have emerged as a pivotal component, offering the flexibility required for complex quantum operations of high performance. In most current architectures of superconducting quantum chips, such couplers are not equipped with dedicated readout circuits to reduce complexity in both design and operation. However, this strategy poses challenges in precise characterization, calibration, and control of the couplers. In this work, we develop a hardware-efficient and robust technique based on adiabatic control to address the above issue. The critical ingredient of this technique is adiabatic swap (aSWAP) operation between a tunable coupler and nearby qubits. Using this technique, we have characterized and calibrated tunable couplers in our chips and achieved straightforward and precise control over these couplers. For example, we have demonstrated the calibration and correction of the flux distortion of couplers. In addition, we have also expanded this technique to tune the dispersive shift between a frequency-fixed qubit and its readout resonator over a wide range.

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