Spin and Charge Transport in Two-Dimensional Materials

Low dimensional materials constitute an exciting and unusually tunable platform for investigation of integer and fractional quantum Hall states. Here I will present our results on transport measurements of high quality graphene and phosphorene devices. In trilayer graphene, we have observed substrate-induced modification of band structures, and a new flavor of quantum Hall effect at the charge neutrality point. In few-layer black phosphorus devices with mobility up to 50,000 cm2/Vs, integer QH states are resolved at a few Tesla, and fractional states at filling factor -4/3 and -0.56±0.1 are observed. Lastly, I will discuss our recent observation of robust long distance spin transport through the antiferromagnetic state in graphene.