IEEE Journal of Solid-State Circuits

Cryogenic CMOS Microwave Signal Selector Using Dual-Stage Injection-Locked Oscillator for Frequency-Multiplexed Qubit Control System

Hiroshi Fuketa, Ippei Akita, H. Koike, Takahiro Mori

Published Feb 4, 2026• 0 citations

Abstract

Cryogenic CMOS (cryo-CMOS) quantum bit (qubit) control circuits are expected to overcome the interconnect complexity problem in large-scale quantum computers. However, since each qubit has a unique frequency for control, many power-hungry oscillators are needed to generate the frequencies at the cryogenic temperature stage of a refrigerator. In this article, to remove the oscillators from the refrigerator, we propose a cryo-CMOS signal selector (SS) consisting of two injection-locked oscillators that extract the specified frequency tone for qubit control from the multitone microwave signal. SS can reduce the power of signal generation for qubit control by 1/30. In addition, we propose a SS with a frequency-doubling function termed FDSS, based on the SS. FDSS can mitigate the local oscillator (LO)-RF leakage in microwave pulse generation for qubit control using direct conversion (DC). We demonstrate a cryo-CMOS DC-based qubit controller using FDSS. The measurement results show that the power dissipation and LO-RF leakage of the proposed qubit controller are reduced by 80% and 20dB, respectively, compared with conventional cryo-CMOS qubit controllers.

DOI: 10.1109/jssc.2026.3658602

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