A 28nm Cryo-CMOS Mixer-first Reflectometer for the FDM Readout of Transmon Qubits

2026-07-07 Hits:

Affiliation of Author(s):University of Electronic Science and Technology of China (UESTC)

Teaching and Research Group:Integrated Physics Group (IPG)

Journal:IEEE Transactions on Microwave Theory and Techniques (TMTT)

Place of Publication:USA

Key Words:quantum computer, Cryo-CMOS, RF reflectometer, Mixer-first receiver, frequency division multiplexing

Abstract:Quantum error correction (QEC) is in-demand for a fault-tolerant quantum computer. Currently, the QEC cycle is bottlenecked by the quantum-bit (qubit) readout. To this end, RF dispersive reflectometry with frequency division multiplexing (FDM) is preferred due to its high fidelity and scalability. However, for a low noise temperature Tnoise, cryogenic low noise amplifiers (cryo-LNA) of classic LNA-first reflectometers require high transconductance efficiency (gm2 /Id). These openloop cryo-LNAs also present limited linearity under large output voltage, resulting in errors of FDM readout.

Note:Accepted on July 7, 2026.

All the Authors:Zizhen Xu,Tianyu Dong,Yijie Chen,Weichen Wang,Yue Yang,Zhixiao Sun,Ruihong Wu,Haichuan Lin,Mingtang Deng

First Author:Yujie Geng

Indexed by:Journal

Correspondence Author:Cheng Wang

Volume:N/A

Issue:N/A

Page Number:1-14

Translation or Not:no

Date of Publication:2026-07-07

Date of Publication:2026-07-07