Tuning Electronic States via Charge Transfer at Graphene/CrSBr Interface

CrSBr is a layered magnetic insulator that provides a versatile platform for engineering quantum properties in two-dimensional heterostructures. When combined with graphene, CrSBr’s strong spin-orbit coupling and anisotropic band structure enable rich interfacial phenomena. Using a combination of angle-resolved photoemission spectroscopy (ARPES), low-energy electron microscopy (LEEM), and density functional theory (DFT), we uncover substantial charge transfer across the interface, leading to significant modifications in electronic structure. The quasi-one-dimensional conduction band of CrSBr becomes partially occupied, exhibiting strong direction-dependent electron mass, while graphene is heavily hole-doped reaching a carrier density of approximately 1.2 ×10¹³ /cm². We also observe signature of direct to indirect band gap transformation of CrSBr. These findings highlight the potential impact of interfacial coupling on band structure and carrier dynamics, offering new opportunities for engineering quantum states in low-dimensional materials.