Marec, Charles, and Gregory’s paper was published in Science today. Congratulations to all coauthors—and a great way to end the year!
An orbital quantum anomalous Hall effect
Quantized Hall effects arise when time reversal symmetry is broken., usually by an externally applied magnetic field. They can also arise at zero magnetic field in a magnetic system with strong spin orbit coupling. In our paper, we showed that this effect can arise from a purely orbital effect, in which electrons spontaneously polarized into valleys in a twisted bilayer graphene sample. The observed quantization persists to record high temperatures to boot!