Hydrodynamics of electron-hole fluid photogenerated in a mesoscopic two-dimensional channel

Abstract

The dynamics of the diffusion flow of holes photoinjected into a mesoscopic GaAs channel of variable width, where they, together with background electrons, form a hydrodynamic electron-hole fluid, is studied using time-resolved microphotoluminescence. It is found that the rate of recombination of photoinjected holes, which is proportional to the rate of their flow, decreases when holes pass through the expanded sections of the channel. In fact, this is the Venturi effect, which consists in a decrease in the velocity of the fluid in the expanded sections of the pipe. Moreover, a non-uniform diffusion velocity profile is observed, similar to the parabolic Hagen-Poiseuille velocity profile, which indicates a viscous hydrodynamic flow. It is shown that in argeement with a theory, the magnetic field strongly suppresses the viscosity of the electron-hole fluid. Additional evidence of the viscous nature of the studied electron-hole fluid is the observed increase in the recombination rate with increasing temperature, which is similar to the decrease in the electrical resistance of viscous electrons with temperature.

7 pages, 4 figures

References in corpus (5)

• Viscous magnetotransport and Gurzhi effect in bilayer electron system
• Hydrodynamics, viscous electron fluid, and Wiedeman-Franz law in 2D semiconductors
• Diffusion of photo-excited holes in viscous electron fluid
• An electron jet pump: The Venturi effect of a Fermi liquid
• Geometric engineering of viscous magnetotransport in a two-dimensional electron system

Cited by in corpus (3)

• Bulk and shear viscosities in multicomponent 2D electron system
• Spectroscopy of Heat Transport and Violation of the Wiedemann--Franz Law in a GaAs Hydrodynamic Mesoscopic Channel
• Electron Hydrodynamics and Bernoulli Effect in Venturi-Shaped 2D Systems