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Cryogenic GaAs high-electron-mobility-transistor amplifier for current noise measurements
Sanghyun Lee1, Masayuki Hashisaka1, Takafumi Akiho1
1NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
The Review of Scientific Instruments
|March 2, 2021
Summary
A novel cryogenic amplifier using a homemade Gallium Arsenide (GaAs) high-electron-mobility transistor (HEMT) significantly improves current-noise measurements in mesoscopic devices. This enhanced sensitivity allows for more efficient and higher-resolution experiments at low temperatures.
Area of Science:
- Condensed Matter Physics
- Quantum Electronics
- Low-Temperature Physics
Background:
- Accurate current-noise measurements are crucial for understanding mesoscopic devices.
- Existing cryogenic amplifiers often have limitations in noise floor and efficiency.
- High-electron-mobility transistors (HEMTs) are promising for low-noise amplification.
Purpose of the Study:
- To develop and evaluate a cryogenic amplifier using a homemade Gallium Arsenide (GaAs) high-electron-mobility transistor (HEMT).
- To assess the suitability of this amplifier for current-noise measurements in mesoscopic devices at dilution-refrigerator temperatures.
- To compare the performance of the homemade HEMT amplifier with a commercial HEMT amplifier.
Main Methods:
- Fabrication of a custom GaAs high-electron-mobility transistor (HEMT).
- Characterization of the HEMT's DC transport properties.
- Measurement of the cryogenic amplifier's gain and noise characteristics.
- Application of the amplifier for current-noise measurements in a quantum point contact device.
Main Results:
- The homemade GaAs HEMT amplifier demonstrated lower noise characteristics compared to a commercial HEMT.
- This resulted in a lower noise floor for the experimental setup.
- The amplifier enabled more efficient current-noise measurements.
- High resolution in current-noise measurements was achieved, comparable to conventional setups.
Conclusions:
- A homemade GaAs HEMT-based cryogenic amplifier is effective for precise current-noise measurements in mesoscopic systems.
- The developed amplifier offers superior noise performance, enhancing experimental efficiency and resolution.
- This technology advances the capability for studying quantum phenomena in mesoscopic devices at cryogenic temperatures.
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