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Superconductor Science and Technology

Corrective-Pulse-Assisted Low-Ic SFQ Ring Oscillator for Cryogenic Microwave Burst Generation

Hongxiang Shen, Nobuyuki Yoshikawa

Published Oct 21, 2026• 0 citations
Publisher

Abstract

Abstract We propose a superconducting ring-oscillator-based SFQ microwave burst generator for scalable cryogenic qubit control. The scheme locally generates high-speed SFQ pulse trains on chip, reducing the need for high-frequency microwave input lines from room temperature. The implemented circuit occupies an area of approximately 0.7 mm×0.7 mm, excluding the TFF array used for low-speed verification, and its static power dissipation is estimated to be 1.14 μW. To suppress timing deviations accumulated in the ring oscillator, corrective pulses are inserted into the generated pulse sequence through low-speed control signals. Continuous-wave measurements verify basic microwave generation, while burst-mode experiments show that properly timed corrective pulses improve firstsideband symmetry and enhance the carrier peak power. Reference-based detrended TIE simulations further verify the existence of effective corrective timing windows in which the residual timing error is reduced below the without-corrective reference. These results indicate that corrective-pulse-assisted SFQ ring oscillators provide a compact and low-power approach for local microwave burst generation in cryogenic qubit-control systems.

DOI
10.1088/1361-6668/aeb769

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