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arXiv · 2407.02722

Pulse Design of Baseband Flux Control for Adiabatic Controlled-Phase Gates in Superconducting Circuits

Qi Ding·Alan V. Oppenheim·Petros T. Boufounos·Simon Gustavsson·Jeffrey A. Grover·Thomas A. Baran·William D. Oliver
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Abstract

Despite progress towards achieving low error rates with superconducting qubits, error-prone two-qubit gates remain a bottleneck for realizing large-scale quantum computers. Therefore, a systematic framework to design high-fidelity gates becomes imperative. One type of two-qubit gate in superconducting qubits is the controlled-phase (CPHASE) gate, which utilizes a conditional interaction between higher energy levels of the qubits controlled by a baseband flux pulse on one of the qubits or a tunable coupler. In this work, we study an adiabatic implementation of CPHASE gates and formulate the design of the control trajectory for the gate as a pulse-design problem. We show in simulation that the Chebyshev-based trajectory can, in certain cases, enable gates with gate infidelity lower by an average of 23.3% when compared to the widely used Slepian-based trajectory.

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Qi Ding, Alan V. Oppenheim, Petros T. Boufounos, Simon Gustavsson, Jeffrey A. Grover, Thomas A. Baran, William D. Oliver. 2024-07-03. Pulse Design of Baseband Flux Control for Adiabatic Controlled-Phase Gates in Superconducting Circuits. https://arxiv.org/abs/2407.02722

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