Detection of graphene’s divergent orbital diamagnetism at the Dirac point

Abstract

Detecting orbital magnetism Graphene’s electronic structure has been predicted to lead to an unusual orbital response to magnetic fields. However, detecting this orbital magnetism is difficult because it is usually masked by the signal stemming from spins. Vallejo Bustamante et al . managed to capture this response by placing two giant magnetoresistance detectors below a sample of graphene sandwiched by layers of hexagonal boron nitride. These detectors picked up a strong diamagnetic response from an undoped sample, consistent with theoretical predictions. The technique may be useful in the investigation of other two-dimensional materials. —JS