500 microkelvin nanoelectronics
Journal article, 2020

Fragile quantum effects such as single electron charging in quantum dots or macroscopic coherent tunneling in superconducting junctions are the basis of modern quantum technologies. These phenomena can only be observed in devices where the characteristic spacing between energy levels exceeds the thermal energy, kBT, demanding effective refrigeration techniques for nanoscale electronic devices. Commercially available dilution refrigerators have enabled typical electron temperatures in the 10 to 100 mK regime, however indirect cooling of nanodevices becomes inefficient due to stray radiofrequency heating and weak thermal coupling of electrons to the device substrate. Here, we report on passing the millikelvin barrier for a nanoelectronic device. Using a combination of on-chip and off-chip nuclear refrigeration, we reach an ultimate electron temperature of Te = 421 ± 35 μK and a hold time exceeding 85 h below 700 μK measured by a self-calibrated Coulomb-blockade thermometer.

Author

Matthew Sarsby

Delft University of Technology

Nikolai Yurttagül

Delft University of Technology

Attila Geresdi

Delft University of Technology

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Nature Communications

2041-1723 (ISSN) 20411723 (eISSN)

Vol. 11 1 1492

Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Condensed Matter Physics

DOI

10.1038/s41467-020-15201-3

PubMed

32198382

More information

Latest update

1/28/2021