Spin–Spin Interaction in ε-VOPO4 through Doping Light Elements

Abstract

Nonmagnetic transition-metal oxides are usually magnetized by doping magnetic metallic elements. Here, we propose an alternative route to achieving magnetization by doping nonmagnetic H and Li atoms. Using vanadium oxide (VOPO4) as an example, we find that the doping of H and Li can effectively localize the excess electrons on V-d orbitals. As such, nonmagnetic ε-VOPO4 is predicted to possess short-range spin–spin interaction. When the doped H2 molecules are bonded with the axial oxygen, we observe a notable charge transfer from oxygen to vanadium. The transferred electrons are localized on two adjacent VO6 octahedrons and induce the spin–spin interaction. We further show that H2 dopants in ε-VOPO4 tend to be dispersed with a homogeneous magnetization. Our results suggest that H2-doped ε-VOPO4 can be utilized in the field of spintronics.