Radiation-induced oscillatory Hall effect in high-mobility GaAs/Al_xGa_1-xAs devices

Abstract

We examine the radiation induced modification of the Hall effect in high-mobility GaAs/Al_xGa_1-xAs devices that exhibit vanishing resistance under microwave excitation. The modification in the Hall effect upon irradiation is characterized by (a) a small reduction in the slope of the Hall resistance curve with respect to the dark value, (b) a periodic reduction in the magnitude of the Hall resistance R_xy that correlates with an increase in the diagonal resistance R_xx, and (c) a Hall resistance correction that disappears as the diagonal resistance vanishes.