▎ 摘 要
The orbital magnetism in spatially varying magnetic fields is studied in monolayer graphene within the effective-mass approximation. We find that, unlike the conventional two-dimensional electron system, graphene with a small Fermi wave number k(F) works as a magnetic shield where the field produced by a magnetic object placed above graphene is always screened by a constant factor on the other side of graphene. The object is repelled by a diamagnetic force from the graphene, as if there exists its mirror image with a reduced amplitude on the other side of graphene. The magnitude of the force is much greater than that of the conventional two-dimensional system. The effect disappears with the increase of k(F).