Role of spin-orbit interaction in the ultrafast demagnetization of small iron clusters
Citation:
Stamenova M, Simoni J, Sanvito S, Role of spin-orbit interaction in the ultrafast demagnetization of small iron clusters, Physical Review B - Condensed Matter and Materials Physics, 94, 1, 2016, 014423 -Download Item:
Abstract:
The ultrafast demagnetization of small iron clusters initiated by an intense optical excitation is studied from
the time-dependent spin density functional theory (TDSDFT). In particular we investigate the effect of the
spin-orbit interaction on the onset of the demagnetization process. It is found that demagnetization occurs
locally, in the vicinity of the atomic sites, and the initial rate of spin loss, coherent with the laser field, is
proportional to the square of the ionic spin-orbit coupling strength
λ
. A simplified quantum spin model comprising
spin-orbit interaction and a time-dependent magnetic field is found to be the minimal model able to reproduce our
ab initio
results. The model predicts the
λ
2
dependence of the onset rate of demagnetization when it is solved
either analytically for the small
t
regime, or numerically integrated in the time domain. Our findings are supported
by additional TDSDFT simulations of clusters made of Co and Ni.
Sponsor
Grant Number
Science Foundation Ireland (SFI)
14/IA/2624
Author's Homepage:
http://people.tcd.ie/sanvitosDescription:
PUBLISHEDExport Date: 5 January 2017
Author: SANVITO, STEFANO
Type of material:
Journal ArticleCollections
Series/Report no:
Physical Review B - Condensed Matter and Materials Physics94
1
Availability:
Full text availableKeywords:
ultrafast demagnetizationDOI:
http://dx.doi.org/10.1103/PhysRevB.94.014423Metadata
Show full item recordLicences: