Magnetic Proximity Effect in Graphene/CrBr3 van der Waals Heterostructures.

2D van der Waals heterostructures serve as a promising platform to exploit various physical phenomena in a diverse range of novel spintronic device applications. Efficient spin injection is the prerequisite for these devices. The recent discovery of magnetic 2D materials leads to the possibility of fully 2D van der Waals spintronics devices by implementing spin injection through the magnetic proximity effect (MPE). Here, the investigation of MPE in 2D graphene/CrBr3 van der Waals heterostructures is reported, which is probed by the Zeeman spin Hall effect through non-local measurements. Quantitative estimation of the Zeeman splitting field demonstrates a significant MPE field even in a low magnetic field. Furthermore, the observed anomalous longitudinal resistance changes at the Dirac point RXX,D with increasing magnetic field near ν = 0 may be attributed to the MPE-induced new ground state phases. This MPE revealed in the graphene/CrBr3 van der Waals heterostructures therefore provides a solid physics basis and key functionality for next-generation 2D spin logic and memory devices.