Spin splitting in graphene is required to develop graphene-based multifunctional spintronic devices with low dissipation and long-distance spin transport. Magnetic proximity effects are a promising route to realize exchange splitting in the material, which is otherwise intrinsically non-spin-polarized. Here, we show that monolayer graphene can be magnetized by coupling to an antiferromagnetic thin film of chromium selenide, resulting in an exchange splitting energy as high as 134 meV at 2 K. This exchange splitting is shown through shifts in the quantum Hall plateau and quantum oscillations in the graphene, and its energy can be modulated through field cooling, with the exchange splitting energy increasing with positive field cooling and decreasing with negative field cooling. Our experimental demonstration of magnetism in graphene at low temperatures is supported by measurements of resistivity dependence on temperature and magneto-optic Kerr measurements.

石墨烯中的自旋分裂是开发低耗散和长距离自旋传输的基于石墨烯的多功能自旋电子器件所必需的。磁性邻近效应是在材料中实现交换分裂的一种有前途的途径，否则该分裂本质上是非自旋极化的。在这里，我们表明，单层石墨烯可以通过耦合到硒化铬的反铁磁薄膜上而被磁化，从而在2 K下产生高达134 meV的交换分裂能。这种交换分裂通过量子霍尔高原和量子的位移来显示。石墨烯发生振荡，其能量可以通过场冷却进行调制，交换分裂能量随正场冷却而增加，随负场冷却而减少。