Curie–Weiss analysis of ferromagnetic and glassy transitions in nanostructured GdAl₂

Authors

D. Williams, University of Nebraska–Lincoln
P. M. Shand, University of Northern IowaFollow
C. Stark, University of Northern Iowa
T. Pekarek, University of North FloridaFollow
R. Brown, University of Nebraska–Lincoln
Lanping Yue, University of Nebraska–LincolnFollow
Diandra Leslie-Pelecky, University of Nebraska -- LincolnFollow

Date of this Version

5-15-2003

Comments

Published by American Institute of Physics. J. Applied Physics 93, 6525-6527 (2003). ©2003 American Institute of Physics. Permission to use. http://jap.aip.org/jap/.

Abstract

Structural inhomogeneity on length scales comparable to magnetic interaction lengths can produce complex magnetic behavior. Crystalline GdAl₂ is a ferromagnet with a Curie temperature of 170 K, while amorphous GdAl₂ thin films exhibit classic spin-glass behavior with a freezing temperature of 16 K. Nanostructured GdAl₂, made by mechanically milling initially crystalline GdAl₂, exhibits ferromagnetic and spin-glass-like transitions; however, the spin-glass-like transition occurs at a higher temperature than the freezing temperature of amorphous GdAl₂ thin films. Curie–Weiss analysis suggests that the paramagnetic-to-ferromagnetic transition is due to the ferromagnetic ordering of small GdAl₂ clusters and that the glassy transition is most likely due to spin-glass-like ordering of a surface/interface phase. ©2003 American Institute of Physics.