Field-driven structural phase transition and sign-switching magnetocaloric effect in Ni-Mn-Sn

TitleField-driven structural phase transition and sign-switching magnetocaloric effect in Ni-Mn-Sn
Publication TypeJournal Article
Year of Publication2007
AuthorsPasquale M, Sasso CP, Giudici L, Lograsso T, Schlagel D
Journal TitleApplied Physics Letters
Volume91
Pages131904
Date PublishedSep
Type of ArticleArticle
ISBN Number0003-6951
Accession NumberISI:000249787000027
Abstract

Depending on the starting equilibrium temperature, the application of a magnetic field on a sample of Ni-Mn-Sn produces sample heating or cooling during adiabatic experiments. The competition between endothermal and exothermal effects is observed close to the martensite-to-austenite magnetostructural phase transition. A model assuming the coexistence of two phases and a field dependence of their volume allows to compute the evolution of entropy and heat capacity during the phase transition. The correct fitting of the results suggests that the field-induced reduction of the martensite-to-austenite transition temperature is responsible for the observed sign switching of the magnetocaloric effect.

DOI10.1063/1.2790829
Alternate JournalAppl. Phys. Lett.