Thin Solid Films 516, 2078 (2008)

N. Moutis, T. Speliotis, I. Panagiotopoulos and M. Ziese

Abstract

In this study the preparation, magnetic and magnetotransport properties of cobalt-iron pyrite (Co_0.5Fe_0.5S₂) thin films are reported. These materials have been recently proposed as a tunable source of highly spin-polarized electrons. The films have been prepared by thermal-sulfidation of Co₅₀Fe₅₀films fabricated by pulsed laser deposition in a sulfur atmosphere at 500 °C, at a pressure of 10⁵ Pa for 12 h. The magnetoresistance curves show an extrinsic negative low field part that is related to alignment of the magnetization between neighbouring grains and scales with M² as in polycrystalline manganites and it is maximized in thinner films. This is superimposed on a positive, linear high field part. The Hall effect has a strong anomalous contribution typical of ferromagnetic materials.