Signal Processing Perspectives on Pulse Design for Two-Qubit Gates in Superconducting Circuits

Although there has been tremendous progress towards achieving low error rates with superconducting qubits, error-prone two-qubit gates remain a bottleneck in realizing large-scale quantum computers. To boost the two-qubit gate fidelity to the highest attainable levels, given limited coherence times, it is essential to develop a systematic framework for optimizing pulse design. In this talk, we formulate the problem of pulse design for two-qubit gates in superconducting qubits within the context of classical signal processing. We take advantage of filter design techniques, including window functions and the Parks-McClellan algorithm to approach the problem. Our research indicates that pulse classes popular in signal processing applications – the Chebyshev pulses and pulses given by the Parks-McClellan algorithm – have the potential to outperform the Slepian pulse, which is currently widely used in quantum experiments.