A novel monoclinic phase and electrically tunable magnetism of van derWaals layered magnet CrTe2

Exploring the novel structural phase of van der Waals (vdW) magnets would promote the development of spintronics. Here, through first-principles calculations, we report a novel monoclinic structure of vdW layered 1T-CrTe 2 , which is one of the popular vdW magnets normally exhibiting a trigonal structure. The new monoclinic phase emerges from a switchable magnetic state between ferromagnetism and antiferromagnetism through changing hole doping concentration, which suggests a practical approach to obtain such a structure. The results of phonon dispersion and energy analysis convince us that the monoclinic structure is a metastable phase even without hole doping. When the hole doping concentration increases, the stability analysis indicates the preference for a novel monoclinic phase rather than a conventional trigonal phase, and meanwhile, the magnetic properties are accordingly tuned. This work provides new insights into the phase engineering of the chalcogenide family and the electrical control of magnetism of vdW layered magnets.