Terahertz generation by GaAs nanowires

Abstract

We report on the emission of terahertz (THz) radiation from p-doped and intentionally undoped GaAs nanowires (NWs). The THz emission has been associated with the contributions of the drift and diffusion currents, excited in the 1D NWs. Taking into account the filling factor, the THz power emission for the NWs is shown to be 40 times more than that of the bulk epitaxial GaAs substrate. By analyzing the non-equilibrium dynamics of the photoinduced carriers in the nanowires, the charge carrier lifetime is shown to be of the order of 3 ns and the drift velocity 105 m/s.