Ab initio density functional calculations of ferromagnetism in low-dimensional nanostructures: From nanowires to nanorods

Autor(en)

Martin Zeleny, Mojmir Sob, Juergen Hafner

Abstrakt

We present ab initio spin-density functional calculations of the electronic and magnetic properties of Fe and Ni nanostructures with a geometry varying between a straight linear wire and a three-dimensional nanorod. With decreasing tension along the axis of the nanostructure we find a series of transitions first from dimerized to periodic and zigzag wires, then to a planar triangular stripe, and further to a nanorod consisting of a periodic stacking of triangular antiprims. In all nanostructures atoms are in a high-moment state, with magnetic moments of about 3.1muB for Fe and about 1muB for Ni. A transition to a low-spin or nonmagnetic state is initiated at a fixed critical value of the interatomic distance, independent of dimension and coordination number. The analysis of the electronic structure shows that already for the one-dimensional nanostructures the ratio between exchange splitting and magnetic moment is close to the universal value I=Delta/ Mtilde 1eV/muB established for bulk itinerant magnets.

Organisation(en)

Computergestützte Materialphysik

Externe Organisation(en)

Masaryk University

Journal

Physical Review B

Band

79

Anzahl der Seiten

10

ISSN

1098-0121

DOI

https://doi.org/10.1103/PhysRevB.79.134421

Publikationsdatum

2009

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/2968dd38-2672-49ed-835a-26c1be2460cb