Cryogenic Transimpedance Amplifier for Condensed Matter Physics Experiments

Characterization of high-impedance cryogenic devices with room temperature electronics is typically limited by low bandwidth and resolution. Placing the amplifiers closer to the device under test, e.g. on 1 K or 4 K plates of dilution refrigirator, was shown to be instrumental to achieve higher measurement bandwidth and sensitivity, see the recent works on spin qubit read-out [1,2].

In a comparison between cryogenic voltage (VA) and transimpedance (TIA) amplifiers, low input and output impedance TIAs offer wider bandwidth compared to high input impedance VAs, which exhibit RC damping due to cable capacitance [3]. Additionally, TIAs using GaAs high-electron-mobility transistors (HEMTs) outperform cryogenic VAs in terms of resolution, thanks to their flat input referred noise floor within the MHz range [1,4].

In this work, we present the Bode plot and noise analysis of common-source VAs and TIAs using commercial GaAs pHEMTs at 300 K, 77 K and 4 K. We begin the TIA design based on [1] and optimize the TIA architecture with the help of SPICE modeling. We discuss the use of our developed cryogenic TIAs for spin qubit read-out, shot-noise measurements in quantum Hall effect and other applications.

[1] Appl. Phys. Lett. 121, 184003 (2022)

[2] PRX Quantum 3, 010352 (2022)

[3] J. Phys. Soc. Jpn. 90, 102001 (2021)

[4] Rev. Sci. Instrum. 85, 054704 (2014)