Tunable magnetism in ferroelectric α -In2Se3 by hole-doping

Two-dimensional (2D) multiferroics attract intensive investigations because of underlying science and their potential applications. Although many 2D systems have been observed/predicted to be ferroelectric or ferromagnetic, 2D materials with both ferroic properties are still scarce. By using first-principles calculations, we predict that hole-doping can induce robust ferromagnetism in 2D ferroelectric α-In2Se3 due to its unique flat band structure, and the Curie temperature (TC) can be much higher than room temperature. Moreover, the doping concentration, strain, and number of layers can effectively modulate the magnetic moment and the TC of the material. Interestingly, strong magnetoelectric coupling is found at the surface of hole doped multilayer α-In2Se3, which allows non-volatile electric control of magnetization. Our work provides a feasible approach for designing/searching 2D multiferroics with great potential in future device applications, such as memory devices and sensors.