Eur. Phys. J. B (2012) 85: 2
https://doi.org/10.1140/epjb/e2011-20332-6

Regular Article

Morphology induced magnetic instabilities on oxide antiferromagnetic surfaces

Surface Physics Division, Saha Institute of Nuclear Physics, 700064 Kolkata, India

^a e-mail: krishna.menon@saha.ac.in

Received: 29 April 2011
Received in final form: 30 September 2011
Published online: 6 January 2012

Abstract

The role of interfacial disorder and roughness has been pointed out several times in ferromagnetic-antiferromagnetic exchange coupled systems. However, effect of surface morphology on magnetic properties of bare antiferromagnetic material has been mostly ignored. Here we report our experimental observations of magnetic instabilities on high temperature air annealed NiO(100) surfaces through treatment of successive vacuum and oxygen annealing above Néel temperature. Preferential spin-orientations are found to be governed by surface morphology with enhanced roughness and oxygen diffusion process. Stable domain distribution has been observed on smoother surfaces, which are found to be mostly inactive to these annealing treatments.