Study of magnetic and transport properties of Bi₂Se₃/FeSe₂ bilayer thin films

Abstract

Thin films of topological insulator (TI) Bi 2 Se 3 were grown onto the surfaces of FeSe 2 layers of different thicknesses on Si (100) substrates by magnetron sputtering, forming bilayer films with smooth surface. Magnetic and transport measurements indicate ferromagnetism in these bilayer samples. Large coercive fields at low-temperatures and a room-temperature magnetic order were observed. Moreover, nonsaturated high-filed linear magnetoresistance (MR) and weak anti-localization effect were found in these bilayer thin films. These results indicate that the bilayer samples could have both strong spin–orbit coupling and ferromagnetic proximity effect, which are the desired features.