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arXiv · 2412.02018

Sensing Few Electrons Floating on Helium with High-Electron-Mobility Transistors

Mayer M. Feldman·Gordian Fuchs·Tiffany Liu·Luke A. D'Imperio·M. David Henry·Eric A. Shaner·Stephen A. Lyon
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Abstract

We report on low-frequency measurements of few electrons floating on superfluid helium using a bespoke cryogenic cascode amplifier circuit built with off-the-shelf GaAs High-Electron-Mobility Transistors (HEMTs). We integrate this circuit with a Charge-Coupled Device (CCD) to transport the electrons on helium and characterize its performance. We show that this circuit has a Signal-to-Noise ratio (SNR) of $\thicksim$ 2$\frac{e}{\sqrt{Hz}}$ at 102 kHz, an order of magnitude improvement from previous implementations and provides a compelling alternative to few electron sensing with high frequency resonators.

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Mayer M. Feldman, Gordian Fuchs, Tiffany Liu, Luke A. D'Imperio, M. David Henry, Eric A. Shaner, Stephen A. Lyon. 2024-12-02. Sensing Few Electrons Floating on Helium with High-Electron-Mobility Transistors. https://arxiv.org/abs/2412.02018

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