Epitaxial stabilization of ferromagnetism in the nanophase of FeGe.
Epitaxial nanocrystals of FeGe have been stabilized on Ge(111). The nanocrystals assume a quasi-one-dimensional shape as they grow exclusively along the <110> direction of the Ge(111) substrate, culminating in a compressed monoclinic modification of FeGe. Whereas monoclinic FeGe is antiferromagnetic in the bulk, the nanowires are surprisingly strong ferromagnets below approximately 200 K with an average magnetic moment of 0.8 microB per Fe atom. Density functional calculations indicate an unusual stabilization mechanism for the observed ferromagnetism: lattice compression destabilizes the antiferromagnetic Peierls-like ground state observed in the bulk while increased p-d hybridization suppresses the magnetic moments and stabilizes ferromagnetism.
Zeng
Changgan
C
Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, USA.
Kent
P R C
PR
Varela
M
M
Eisenbach
M
M
Stocks
G M
GM
Torija
Maria
M
Shen
Jian
J
Weitering
Hanno H
HH