Abstract
Large-scale growth of two-dimensional (2D) ferromagnetic thin films will provide an ideal platform for studying 2D magnetism and active spintronic devices. However, controllable growth of 2D ferromagnets over large areas faces tremendous challenges. Herein, we report a large-area growth of 2D ferromagnetic single-crystal thin films Cr4Te5 on Al2O3 (0001) substrates using pulsed laser deposition. X-ray diffraction patterns and atomic force microscopy detection confirm that all thin films are high quality epitaxy together with atom-level smooth. Magnetic measurements show the persistence of ferromagnetic ordering state up to above room temperature, with a Curie temperature 320 K, atomic magnetic moment 0.307µB/Cr, and the easy-magnetization axis in film plane. Comparing bulk Cr4Te5 single-crystal, the critical exponent β=0.491 indicates that the magnetic interactions of thin film obey mean-field model rather than 3D Heisenberg model. This work will open a avenue for growing large-scale 2D ferromagnet and developing room temperature 2D magnet-based nanodevices.
