Field step size and temperature effects on the character of the magnetostructural transformation in a Gd5Ge4 single crystal

TitleField step size and temperature effects on the character of the magnetostructural transformation in a Gd5Ge4 single crystal
Publication TypeJournal Article
Year of Publication2007
AuthorsOuyang ZW, Pecharsky VK, Gschneidner KA, Schlagel DL, Lograsso TA
Journal TitlePhysical Review B
Volume76
Pages134406
Date PublishedOct
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberISI:000250619800064
Keywordsgd-5(si2ge2), gd-5(sixge1-x)(4), ge, transition
Abstract

The critical magnetic fields required to induce the magnetostructural transformation below similar to 30 K in Gd5Ge4 are dependent on the size of the magnetic-field step employed during isothermal measurements of magnetization: the smaller the step, the lower the critical field. The influence of the magnetic-field step size on the character of the magnetostructural transition in Gd5Ge4 diminishes as temperature increases, nearly disappearing above similar to 30 K. Decreasing the size of the field step also leads to the formation of multiple steps in the magnetization. The steps are reproducible in the same sample at low temperatures (below similar to 9 K) but they become stochastic and irreproducible at high temperatures (above similar to 20 K). The varying dynamics of both the magnetization and demagnetization processes is associated with approaching true equilibrium states and, therefore, reduction of the size of the magnetic-field step at low temperatures plays a role similar to the dominant role of thermal fluctuations at high temperatures. Similar phenomena are expected to occur in other martensiticlike systems, e.g., the manganites.

DOI10.1103/PhysRevB.76.134406
Alternate JournalPhys. Rev. B