Abstract
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.
| Original language | English |
|---|---|
| Article number | 1492 |
| Journal | Nature Communications |
| Volume | 11 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 20 Mar 2020 |
| MoE publication type | A1 Journal article-refereed |
Funding
This work has been supported by the Netherlands Organization for Scientific Research (NWO) and Microsoft Corporation Station Q. A.G. acknowledges funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme, grant number 804988. Open access funding was provided by Chalmers University of Technology.
Keywords
- Nanoelectronics