Adiabatic demagnetization refrigeration to millikelvin temperatures with the distorted square lattice magnet NaYbGeO4

  • We report the synthesis, characterization, low-temperature magnetic, and thermodynamic measurements of the millikelvin adiabatic demagnetization refrigeration (mK-ADR) candidate material NaYbGeO4 which exhibits a distorted square lattice arrangement of YbO6 magnetic units. Magnetization and specific heat indicate weakly interacting effective spin-1/2 moments below 10 K, with a Curie-Weiss temperature of only 15 mK, that can be polarized by magnetic fields of order 1 T. For the ADR performance test, we start the demagnetization from 5 T at a temperature of ∼2K and reach a minimum temperature of 150 mK at zero field. The warming curve indicates a sharp magnetic transition in the heat capacity at 210 mK, implying only weak magnetic frustration. The entropy density of SGS≃101 mJK−1cm-3 and hold time below 2 K of 220 min are competitive while the minimal temperature is higher compared to frustrated Ytterbium-oxide ADR materials studied under similar conditions.

Download full text files

Export metadata


Number of document requests

Additional Services

Share in Twitter Search Google Scholar
Author:U. Arjun, K. M. Ranjith, Anton JescheORCiDGND, Fabian Hirschberger, D. D. Sarma, Philipp GegenwartORCiDGND
Frontdoor URL
Parent Title (English):Physical Review B
Publisher:American Physical Society (APS)
Place of publication:College Park, MD
Year of first Publication:2023
Publishing Institution:Universität Augsburg
Release Date:2023/12/12
First Page:224415
Institutes:Mathematisch-Naturwissenschaftlich-Technische Fakultät
Mathematisch-Naturwissenschaftlich-Technische Fakultät / Institut für Physik
Mathematisch-Naturwissenschaftlich-Technische Fakultät / Institut für Physik / Lehrstuhl für Experimentalphysik VI
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik
Licence (German):Deutsches Urheberrecht