On-chip magnetic cooling of a nanoelectronic device

Abstract

We demonstrate significant cooling of electrons in a nanostructure below 10 mK by demagnetisation of thin-film copper on a silicon chip. Our approach overcomes the typical bottleneck of weak electron-phonon scattering by coupling the electrons directly to a bath of refrigerated nuclei, rather than cooling via phonons in the host lattice. Consequently, weak electron-phonon scattering becomes an advantage. It allows the electrons to be cooled for an experimentally useful period of time to temperatures colder than the dilution refrigerator platform, the incoming electrical connections, and the host lattice. There are efforts worldwide to reach sub-millikelvin electron temperatures in nanostructures to study coherent electronic phenomena and improve the operation of nanoelectronic devices. On-chip magnetic cooling is a promising approach to meet this challenge. The method can be used to reach low, local electron temperatures in other nanostructures, obviating the need to adapt traditional, large demagnetisation stages. We demonstrate the technique by applying it to a nanoelectronic primary thermometer that measures its internal electron temperature. Using an optimised demagnetisation process, we demonstrate cooling of the on-chip electrons from 9 mK to below 5 mK for over 1000 seconds.

arXiv comment9 pages, 5 figures

References in corpus (10)

• Opportunities for mesoscopics in thermometry and refrigeration: Physics and applications
• Single-electron current sources: towards a refined definition of ampere
• Observations and modeling of large area normal-metal/insulator/superconductor refrigerator cooling from 300 mK to below 100 mK
• Nanoelectronic thermometers optimised for sub-10 millikelvin operation
• Metallic Coulomb Blockade Thermometry down to 10 mK and below
• Dry demagnetization cryostat for sub-millikelvin helium experiments: refrigeration and thermometry
• Accurate Coulomb Blockade Thermometry up to 60 Kelvin
• A microkelvin cryogen-free experimental platform with integrated noise thermometry
• Ex-situ Tunnel Junction Process Technique Characterized by Coulomb Blockade Thermometry
• One and two dimensional tunnel junction arrays in weak Coulomb blockade regime-absolute accuracy in thermometry

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• Magnetocaloric and electrocaloric properties of the Hubbard pair cluster
• Thermal transport in nanoelectronic devices cooled by on-chip magnetic refrigeration
• Coulomb blockade thermometry beyond the universal regime
• On-chip quantum confinement refrigeration overcoming electron-phonon heat leaks
• Influence of device non-uniformities on the accuracy of Coulomb blockade thermometry
• Coulomb Blockade Thermometry on a Wide Temperature Range