Structure and magnetism of MnAu nanoclusters

Authors

X. Wei, University of Nebraska-Lincoln
Damien Le Roy, University of Nebraska-LincolnFollow
Ralph Skomski, University of Nebraska - LincolnFollow
Xingzhong Li, University of Nebraska - LincolnFollow
Zhiguang Sun, University of Nebraska - LincolnFollow
Jeffrey E. Shield, University of Nebraska-LincolnFollow
M. J. Kramer, Ames Laboratory, Ames, Iowa
David J. Sellmyer, University of Nebraska-LincolnFollow

Date of this Version

2011

Citation

JOURNAL OF APPLIED PHYSICS 109, 07B523 (2011)

doi:10.1063/1.3559502

Comments

Copyright © 2011 American Institute of Physics

Abstract

Equiatomic MnAu clusters with average sizes of 4 and 10 nm are produced by inert-gas condensation. As-produced clusters are used to form both dense cluster films and films with clusters embedded in a W matrix with a cluster volume fraction of 25%. Both structure and magnetism are size-dependent. Structural analysis of the 10 nm clusters indicate a distorted tetragonal body-centered cubic structure with lattice parameters a=0.315 and c=0.329 nm. The 4 nm clusters have a partially ordered tetragonal L10 structure with lattice parameters a=0.410 nm and c=0.395 nm. Magnetic properties of the clusters show evidence at low temperatures of mixed ferromagnetic and antiferromagnetic interactions and ordering as well as paramagnetic spins. Saturation moments are as large as 0.54 μ_B per average Mn atom. The results are compared with earlier theoretical calculations on bulk MnAu.