Exchange coupling and spin structure in cobalt-on-chromia thin films

¹ School of Basic Sciences, Indian Institute of Technology Mandi - Mandi, Himachal Pradesh 175001, India
² Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska Lincoln, NE 68588, USA
³ Graduate School of Science, Hiroshima University - Higashi-Hiroshima, Hiroshima 739-6526, Japan
⁴ Hiroshima Synchrotron Radiation Center (HSRC), Hiroshima University - 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan

^(a) arti.kashyap@gmail.com

Received: 13 April 2016
Accepted: 8 July 2016

Abstract

Cobalt-chromia interface exchange interactions in the Co-on-Cr₂O₃(0001) system are investigated. Density-functional theory predicts the exchange coupling at the interface to be antiferromagnetic, in agreement with earlier experimental results. The spin-polarized photoemission spectra reveal both perpendicular and in-plane magnetization components, in the cobalt adlayer on chromia. A magnetization canted with respect to the surface normal, inferred from the presence of remnant spin polarization both in the plane of the cobalt film and along the surface normal may be understood as a micromagnetic canting effect involving magnetostatic self-interaction and exchange coupling between Co and Cr₂O₃.