Abstract-Edge currents driven by terahertz radiation in graphene in quantum Hall regime

Helene Plank, M V Durnev, Susanne Candussio, Johanna Pernul, Kathrin-Maria Dantscher, Erwin Mönch, Andreas Sandner, Jonathan Eroms, Dieter Weiss, Vasily V Belkov

http://iopscience.iop.org/article/10.1088/2053-1583/aae39c

We observe that the illumination of  graphene in the quantum Hall regime with polarized terahertz laser radiation results in a direct edge current. This photocurrent is caused by an imbalance of persistent edge currents, which are driven out of thermal equilibrium by indirect transitions within the chiral edge channel. The direction of the edge photocurrent is determined by the polarity of the external magnetic field, while its magnitude depends on the radiation polarization. The microscopic theory developed in this paper describes well the experimental data.