NANOTEMP · Nanoscale Devices for Ultralow Temperature Thermometry
FP7 — People (Marie Curie Actions)
- Duration
- 2013-08-01 → 2017-07-31
- EU contribution
- €100,000
- Participants
- 1
- Scheme
- MC-CIG
Lines connect the coordinator with its partners.
Results in brief
Nanoscale Devices for Ultralow Temperature Thermometry
Studies of nanoelectronic devices at low temperatures have produced many fundamental discoveries in physics and material science and have the potential to enable new applications such as future metrological standards and sensors that are enhanced by the quantum-mechanical nature of their operation. For quantum-enhanced applications, it is often important to cool the devices far below 1 Kelvin, approaching temperatures of a few millikelvin. The goal of this project was to address outstanding challenges in nanoelectronic thermometry and to provide new tools and techniques for researchers working at temperatures of a few millikelvin and below. One outstanding challenge in this regime is how to effectively cool electrons in nanoelectronic structures. Until recently, the record low temperature in such structures had been 4 millikelvin for over 10 years. During this project we were been able to break this barrier, reaching temperatures significantly below 2 millikelvin. This was achieved using a new cooling technique that has the potential to reach sub-millikelvin temperatures, combined with with reliable thermometry of on-chip electron temperature. Another challenge at ultralow temperatures is understanding the behaviour of the refrigerant, which can be a metal (for demagnetization cooling) or a mixture of superfluid helium-3 and helium-4 (for dilution refrigeration). Probing superfluid helium has been possible for many years using macroscopic mechanical objects. Now it is possible to use techniques from nanotechnology to create smaller probes that will provide new information about the superfluid. During this project we succeeded in measuring the damping of a nanomechanical resonator immersed in superfluid helium-4. The project has provided valuable opportunities for the fellow to form new collaborations in Europe and to reintegrate within the UK and EU research community. As well as academic collaborations, the project has facilitated new industrial collaborations that would otherwise not have been possible.
Data: CORDIS, © European Union
Project objective
Developments in low temperature technology heave reached the point where temperatures around 1 mK can be reached in commercially available systems, typically based on a 3He-4He dilution refrigerator. In the lab, nuclear demagnetisation refrigeration pushes this boundary lower: nuclear spin systems have been cooled to the nanokelvin regime, while the lowest temperature ever measured for electrons in a material is around 10 microkelvin.The availability of commercial millikelvin refrigerators has driven numerous discoveries in physics and materials science and continues to facilitate research on materials, fundamental physics, and quantum technologies. All of these fields would benefit from access to lower temperatures, but this transition is challenging and requires technological step-changes. This is partly because the commercial workhorse technology, the dilution refrigerator, is not a practical solution. (The record temperature for a dilution refrigerator is 1.75 mK and has been for over a decade.) More significant obstacles are the lack of reliable thermometry, particularly for electrons in nanoelectronic devices, and the challenge of making low temperature thermal contact between the system being studied and a nuclear demagnetisation refrigerator.This project will address several challenges to working below 1 mK, with the aim of opening the regime to studies of nanoelectronics, nanomechanics, and materials science. This will be achieved by developing two new thermometers: one for measuring the temperature of electrons in nanoscale samples, and one for improved measurements of the temperature of superfluid helium-3. We will also develop a platform to make thermal connection to nanoscale samples, with a particular focus on cooling incoming electrical connections. Through these developments, this project aims to move nanoscale science firmly into the sub-millikelvin regime, and to bring the benefits of nanotechnology to existing areas of low temperature physics.
Original text from CORDIS.
Participants
- UNIVERSITY OF LANCASTER · LANCASTERCoordinatorUnited Kingdom
Links
Data: CORDIS, © European Union