Strain Induced High Curie Temperature in Molecular Beam Epitaxy Grown Cr2Te3 Thin Films with Perpendicular Magnetic Anisotropy*

In this work, Cr2Te3 thin films with high Curie temperature from 191 to 280K on Al2O3 (0001) substrates were grown by Molecular Beam Epitaxy technique. In-situ long streaky reflection high energy electron diffraction patterns indicate that the Cr2Te3 thin films were grown with an atomic flat surface and single crystalline quality. X-ray diffraction study shows a significant increase of lattice constant of Cr2Te3 thin films along [001] direction. A ZnSe capping layer was used for tuning the compressive strain in Cr2Te3 thin films, resulting in a change of lattice constant along [001] orientation. A spin glass-like magnetic behavior is systematically investigated by zero-field-cooling and field-cooling magnetization characterizations. A strong perpendicular magnetic anisotropy is identified by measuring the field dependent magnetization curves along different crystalline directions.