Diffusion of Photoexcited Holes in a Viscous Electron Fluid
Yu. A. Pusep, M. D. Teodoro, V. Laurindo, E. R. Cardozo de Oliveira, G. M. Gusev, A. K. Bakarov
Abstract
The diffusion of photogenerated holes is studied in a high-mobility mesoscopic GaAs channel where electrons exhibit hydrodynamic properties. It is shown that the injection of holes into such an electron system leads to the formation of a hydrodynamic three-component mixture consisting of electrons and photogenerated heavy and light holes. The obtained results are analyzed within the framework of ambipolar diffusion, which reveals characteristics of a viscous flow. Both hole types exhibit similar hydrodynamic characteristics. In such a way the diffusion lengths, ambipolar diffusion coefficient, and the effective viscosity of the electron-hole system are determined.