Millikelvin cooling by heavy-fermion-based tunnel junctions

Journal Article · Mon Dec 28 04:00:00 EST 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4938477· OSTI ID:22493102

Prest, Martin; Min, Gao ^[1]; Whall, Terry ^[2]

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1. School of Engineering, Cardiff University, Cardiff CF24 3AA (United Kingdom)
2. Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)

This paper addresses a high-performance electron-tunneling cooler based on a novel heavy-fermion/insulator/superconductor junction for millikelvin cooling applications. We show that the cooling performance of an electronic tunneling refrigerator could be significantly improved using a heavy-fermion metal to replace the normal metal in a conventional normal metal/insulator/superconductor junction. The calculation, based on typical parameters, indicates that, for a bath temperature of 300 mK, the minimum cooling temperature of an electron tunneling refrigerator is reduced from around 170 mK to below 50 mK if a heavy-fermion metal is employed in place of the normal metal. The improved cooling is attributed to an enhancement in electron tunneling due to the existence of a resonant density of states at the Fermi level.

• OSTI ID: 22493102
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 24 Vol. 118; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COOLING
DENSITY OF STATES
ELECTRONS
FERMI LEVEL
METALS
SUPERCONDUCTING JUNCTIONS
TUNNEL EFFECT