Strong magnetocaloric effect induced by spin reorientation transitions in epitaxial Ho thin films
Résumé
Magnetocaloric effect (MCE) in an antiferromagnetic holmium (Ho) film is studied near the spin reorientation temperatures. A series of magnetization isotherms from 60 to 150 K around the Néel temperature, T N ≈ 130 K were recorded for both in-plane and out-of-plane magnetic field orientations. A change in entropy, S M of-5 J/kgK was found near T N for an in-plane field orientation. A large change in S M of −11.8 J/kg K due to a fan-helix spin transition at T = 90 K is observed for an in-plane field orientation. Spin transition at both T N and at the fan-helix transition exhibit larger MCE in the in-plane field orientations in comparison with the perpendicular orientation. The value of the refrigerant capacity extracted from the temperature dependence of S M (T) is found to be larger for the "in-plane" orientation by a factor of two.
Domaines
Physique [physics]Origine | Fichiers produits par l'(les) auteur(s) |
---|