Eur. Phys. J. B (2018) 91: 62
https://doi.org/10.1140/epjb/e2018-80513-3

Regular Article

Magnetism of CrO overlayers on Fe(001)bcc surface: first principles calculations

¹ Facultad de Ciencias Físico-Matemáticas de la Universidad Autónoma de Sinaloa, Av. Las Americas y Blvd. Universitarios, Colonia Universitaria, C.P. 80010 Culiacán Sinaloa, Mexico
² UFR de Physique et d’Ingénierie, 3 rue de l’Université, 67000 Strasbourg, France

^a e-mail: smeza@uas.edu.mx

Received: 7 September 2017
Received in final form: 1 December 2017
Published online: 6 April 2018

Abstract

Riva et al. [Surf. Sci. 621, 55 (2014)] as well as Calloni et al. [J. Phys.: Condens. Matter 26, 445001 (2014)] have studied the oxydation of Cr films deposited on Fe(001)bcc through low-energy electron diffraction, Auger electron spectroscopy and scanning tunneling microscopy. In the present work we perform a density functional approach within Quantum Expresso code in order to study structural and magnetic properties of CrO overlayers on Fe(001)bcc. The calculations are performed using DFT+U. The investigated systems include O/Cr/Fe(001)bcc, Cr/O/Fe(001)bcc, Cr_0.25O_0.75/Fe(001)bcc, as well as the O coverage O_x/Cr/Fe(001)bcc (x = 0.25; 0.50). We have found that the ordered CrO overlayer presents an antiferromagnetic coupling between Cr and Fe atoms. The O atoms are located closer to the Fe atoms of the surface than the Cr atoms. The ground state of the systems O/Cr/Fe(001)bcc and Cr/O/Fe(001)bcc corresponds to the O/Cr/Fe(001)bcc system with a magnetic coupling c(2 × 2). The effect of the O monolayer on Cr/Fe(001)bcc changes the ground state from p(1 × 1) ↓ to c(2 × 2) and produces an enhancement of the magnetic moments. The O_x overlayer on Cr/Fe(001)bcc produces an enhancement of the Cr magnetic moments.