Document IIF

Numerical modelling and experimental validation of adiabatic demagnetization refrigeration at sub-Kelvin temperatures.

Résumé

Adiabatic demagnetization refrigeration (ADR) offers helium-3-free access to millikelvin temperatures and is therefore ideally suited as cooling platform for scaled-up quantum technology applications. Designing and optimizing ADR stages for the sub-100 mK regime requires quantitative models capable of predicting system performance under realistic operating conditions. At these temperatures, thermal boundary resistance, strongly nonlinear magnetocaloric behaviour, eddy current heating, and parasitic heat loads become dominant effects that simple analytical estimates cannot capture. This paper presents a coupled numerical model for the thermal dynamics of the refrigerant, i.e. a paramagnetic salt, and the thermal interface structure, i.e. a copper matrix, in a single ADR stage and validates it against experimental measurements. The two key material inputs, the field-dependent specific heat of the salt and the temperature dependent thermal conductance of the salt-copper interface, are independently characterized for Ferric Ammonium Alum (FAA) and Chromic Potassium Alum (CPA). Interface conductance measurements confirm a T3 dependence for both materials, consistent with acoustic mismatch theory. Specific heat measurements validate the magnetocaloric model with literature parameters across the full field range investigated. The model accurately reproduces temperature evolution during magnetic field ramps as well as magnetic field decay while stabilizing a temperature for both materials.
 

Documents disponibles

Format PDF

Pages : 10 p.

Disponible

  • Prix public

    20 €

  • Prix membre*

    15 €

* meilleur tarif applicable selon le type d'adhésion (voir le détail des avantages des adhésions individuelles et collectives)

Détails

  • Titre original : Numerical modelling and experimental validation of adiabatic demagnetization refrigeration at sub-Kelvin temperatures.
  • Identifiant de la fiche : 30035057
  • Langues : Anglais
  • Sujet : Technologie
  • Source : 11th IIR Conference on Solid-State Cooling, Heating and Energy Harvesting.
  • Date d'édition : 07/06/2026
  • DOI : http://dx.doi.org/10.18462/iir.thermag.2026.0012

Liens


Voir d'autres communications du même compte rendu (29)
Voir le compte rendu de la conférence