A microkelvin magnetic flux noise thermometer

• Verfasst von: Rothfuß, Daniel Simon [VerfasserIn]
• Verfasst von: Reiser, Andreas [VerfasserIn]
• Verfasst von: Fleischmann, Andreas [VerfasserIn]
• Verfasst von: Enss, Christian [VerfasserIn]
• Titel: A microkelvin magnetic flux noise thermometer
• Verf.angabe: D. Rothfuß, A. Reiser, A. Fleischmann, C. Enss
• E-Jahr: 2014
• Jahr: 17 March 2014
• Umfang: 8 S.
• Fussnoten: Gesehen am 24.08.2020
• Titel Quelle: Enthalten in: Journal of low temperature physics
• Ort Quelle: Dordrecht : Springer Science + Business Media B.V., 1969
• Jahr Quelle: 2014
• Band/Heft Quelle: 175(2014), 5, Seite 776-783
• ISSN Quelle: 1573-7357
• DOI: doi:10.1007/s10909-014-1146-0
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1727682548

Abstract

Due to its non-driven nature, noise thermometry intrinsically is the method of choice when minimal heat input during the temperature measurement is required. Our noise thermometer, experimentally characterized for temperatures between 42 $${{\upmu }}$$μK and 0.8 K, is a magnetic Johnson noise thermometer. The noise source is a cold-worked high purity copper cylinder, 5 mm in diameter and 20 mm long. The magnetic flux fluctuations generated by the electrons’ Brownian motion is measured inductively by two dc-SQUID magnetometers simultaneously. Cross-correlation of the two channels leads to reduction of parasitic noise by more than one order of magnitude which allows for measuring the tiny noise powers at microkelvin temperatures.