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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Superconducting quantum interference devices based set-up for probing current noise and correlations in
A H Pfeffer1, B Kaviraj, O Coupiac
1SPSMS/LaTEQS, UMR-E 9001, CEA-INAC, and Université Joseph Fourier, Grenoble, France.
The Review of Scientific Instruments
|December 5, 2012
Summary
We developed a new low-temperature setup for precise current fluctuation measurements in devices. This system uses superconducting quantum interference devices (SQUIDs) to accurately measure noise and correlations, validating its low intrinsic noise.
Area of Science:
- Condensed Matter Physics
- Experimental Physics
- Quantum Electronics
Background:
- Precise measurement of current fluctuations is crucial for understanding electronic transport in mesoscopic devices.
- Existing setups often face limitations in sensitivity and the ability to measure correlations across multiple terminals.
Purpose of the Study:
- To introduce a novel experimental setup for high-precision current fluctuation measurements at millikelvin temperatures.
- To characterize the noise and cross-correlation properties of the new measurement system.
- To validate the setup's performance using macroscopic resistors.
Main Methods:
- Implementation of a cryogenic system operating at 30 mK.
- Utilizing three low-noise superconducting quantum interference devices (SQUIDs) as current amplifiers.
- Connecting SQUID input coils to each terminal of the sample for simultaneous current acquisition.
- Calibration using low-impedance macroscopic resistors to determine noise levels and cross-correlations.
Main Results:
- Successful calibration of the setup demonstrating low intrinsic noise levels.
- Absence of measurement-scheme-induced correlations confirmed.
- Analysis of noise and correlations as a function of DC current.
- Estimation of electronic temperatures in macroscopic resistors.
Conclusions:
- The new experimental setup enables precise measurements of current fluctuations, noise, and cross-correlations in three-terminal devices at ultra-low temperatures.
- The system's low intrinsic noise and lack of spurious correlations are validated.
- The setup provides a reliable platform for investigating quantum transport phenomena and electronic properties of materials.
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