Micromagnetic modelling and magneto-optical characterization of Ni/V2O3 hybrid structures

Magnetic behaviour of five bi-layer V2O3/Ni thin film samples sputtered on sapphire, Al2O3, were investigated using MOKE (magneto-optic Kerr effect). Three samples show a fourfold symmetry in coercivity with very small but similar change in magnetic remanence. For comparison micromagnetic simulations were done in Mumax3. The samples have a well defined growth direction, [111], so simulations were setup to replicate this. Nickel is a cubic crystal with easy axes <111>, hard axes <100> and medium axes <110>. In the simulations an external magnetic field was applied and then rotated in-plane as was done in the MOKE measurements. The result are hysteresis loops as a function of azimuthal angle yielding the normalized magnetic remanence and coercive field. This was done for two sample sizes with number of cells in x-, yand z- direction 128x128x2 and 256x256x2 both having cell size 4x4x10nm. The results did not change when sample size was increased. These simulations were done both for growth direction [111] and [100] out of plane. Quantitatively the results from simulations agree with magneto-crystalline energy for nickel, both when rotated around [111] and [100], showing a sixfold and fourfold symmetry respectively. The measured samples don’t show this sixfold symmetry.

Author dc:creator

• Björn Áki Jósteinsson 1996-

Contributors dc:contributor

• Háskóli Íslands

• Verkfræðileg eðlisfræði

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/1946/35490

OAI identifier oai:identifier

oai:skemman.is:1946/35490