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Updated: Oct 4, 2025
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
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Cooling low-dimensional electron systems into the microkelvin regime.
Lev V Levitin1, Harriet van der Vliet2,3, Terje Theisen2
1Department of Physics, Royal Holloway, University of London, Egham, TW20 0EX, UK. l.v.levitin@rhul.ac.uk.
Nature Communications
|February 4, 2022
Summary
Researchers achieved ultra-low electron temperatures below 1 millikelvin in two-dimensional electron gases (2DEGs). This breakthrough enables the study of novel quantum phenomena and correlated electron states in nanoelectronic devices.
Area of Science:
- Condensed Matter Physics
- Quantum Materials Science
Background:
- Two-dimensional electron gases (2DEGs) in semiconductor heterostructures exhibit complex correlated phases at low temperatures.
- These 2DEGs are crucial for exploring topological and spin-correlated states, with potential spintronic applications.
Purpose of the Study:
- To overcome the challenge of cooling 2DEGs to sub-millikelvin temperatures.
- To establish a platform for investigating new quantum phenomena and advanced nanoelectronic devices.
Main Methods:
- Immersion of the 2DEG device in liquid helium-3 (³He).
- Cooling via nuclear adiabatic demagnetization of copper.
- Temperature measurement using electronic noise in a gold wire connected to the 2DEG.
Main Results:
- Achieved a record low electron temperature of 0.9 ± 0.1 millikelvin (mK).
- Demonstrated effective screening and filtering techniques for ultra-low temperature measurements.
- Indicated potential for further temperature reduction.
Conclusions:
- Successfully cooled 2DEGs to below 1 mK, a significant technological advancement.
- This platform facilitates the observation of new quantum phenomena and the development of correlated electron-based nanoelectronics.
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