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arXiv · 2102.04364

Compact gate-based read-out of multiplexed quantum devices with a cryogenic CMOS active inductor

L. Le Guevel·G. Billiot·S. De Franceschi·A. Morel·X. Jehl·A. G. M. Jansen·G. Pillonnet
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Abstract

In the strive for scalable quantum processors, significant effort is being devoted to the development of cryogenic classical hardware for the control and readout of a growing number of qubits. Here we report on a cryogenic circuit incorporating a CMOS-based active inductor enabling fast impedance measurements with a sensitivity of 10 aF and an input-referred noise of 3.7 aF/sqrt(Hz). This type of circuit is especially conceived for the readout of semiconductor spin qubits. As opposed to commonly used schemes based on dispersive rf reflectometry, which require mm-scale passive inductors, it allows for a markedly reduced footprint (50$\mu$m $\times$ 60$\mu$m), facilitating its integration in a scalable quantum-classical architecture. In addition, its active inductor results in a resonant circuit with tunable frequency and quality factor, enabling the optimization of readout sensitivity.

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L. Le Guevel, G. Billiot, S. De Franceschi, A. Morel, X. Jehl, A. G. M. Jansen, G. Pillonnet. 2021-02-08. Compact gate-based read-out of multiplexed quantum devices with a cryogenic CMOS active inductor. https://arxiv.org/abs/2102.04364

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