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arXiv · 1907.04818

Time-domain characterization and correction of on-chip distortion of control pulses in a quantum processor

M. A. Rol·L. Ciorciaro·F. K. Malinowski·B. M. Tarasinski·R. E. Sagastizabal·C. C. Bultink·Y. Salathe·N. Haandbaek·J. Sedivy·L. DiCarlo
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Abstract

We introduce Cryoscope, a method for sampling on-chip baseband pulses used to dynamically control qubit frequency in a quantum processor. We specifically use Cryoscope to measure the step response of the dedicated flux control lines of two-junction transmon qubits in circuit QED processors with the temporal resolution of the room-temperature arbitrary waveform generator producing the control pulses. As a first application, we iteratively improve this step response using optimized real-time digital filters to counter the linear-dynamical distortion in the control line, as needed for high-fidelity, repeatable one- and two-qubit gates based on dynamical control of qubit frequency.

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M. A. Rol, L. Ciorciaro, F. K. Malinowski, B. M. Tarasinski, R. E. Sagastizabal, C. C. Bultink, Y. Salathe, N. Haandbaek, J. Sedivy, L. DiCarlo. 2019-07-10. Time-domain characterization and correction of on-chip distortion of control pulses in a quantum processor. https://doi.org/10.1063/1.5133894

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