Surface enhancement of soft-mode transformation in Ni2MnGa

Autor:	G Landmesser, Uwe Klemradt, Trevor R Finlayson, Robert L. Johnson
Rok vydání:	2007
Předmět:	Crystallography Materials science Physics and Astronomy (miscellaneous) Ferromagnetism Condensed matter physics Phonon Transition temperature Thermal Soft modes Thermal diffusivity Polarization (waves) Actuator
Zdroj:	Applied Physics Letters. 90:021907
ISSN:	1077-3118 0003-6951
DOI:	10.1063/1.2431459
Popis:	Ni2MnGa exhibits both shape memory behavior, owing to a diffusionless structural transformation, and ferromagnetism, leading to magnetic-field based actuator applications. The current interest in highly miniaturized mechanical devices raises the question whether the structural phase transformations of Ni2MnGa are affected by the presence of interfaces. Thermal diffuse scattering of x-rays from the soft phonon mode which drives the transformation was analyzed for depths from 3.5nmto6.4μm beneath a clean (001) surface. The authors find an enhancement of the transition temperature by about 15K in the near-surface region, but no evidence for a change of the soft-mode polarization.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f24e3e0ad5ae7470b7b6820970825f15 https://doi.org/10.1063/1.2431459 Zobrazit plný text záznamu