Nonvolatile switchable half-metallicity and magnetism in the MXene Hf 2 MnC 2 O 2 /Sc 2 CO 2 multiferroic heterostructure.

Nonvolatile electrical control of two-dimensional (2D) van der Waals (vdW) magnetism is important for spintronic devices. Here, using first-principles calculations, we systematically investigated the magnetic properties of the MXene Hf 2 MnC 2 O 2 combined with the ferroelectric MXene Sc 2 CO 2 . When flipping the electric polarization of Sc 2 CO 2 , a transition between a semiconductor and a half-metal occurs in the Hf 2 MnC 2 O 2 monolayer. Moreover, the ferromagnetic exchange parameter J 1 can be enhanced to 9.67 meV under polarized P ↑ of Sc 2 CO 2 , much larger than those of the pristine Hf 2 MnC 2 O 2 monolayer and Hf 2 MnC 2 O 2 /Sc 2 CO 2 - P ↓. In addition, the easy magnetization axis of the Hf 2 MnC 2 O 2 monolayer is also dependent on the polarization orientation of Sc 2 CO 2 . Our results indicate a multiferroic heterostructure based on MXenes, offering an effective way for obtaining nonvolatile electrical control of electronic and magnetic properties.