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arXiv · 2204.00041

Diffusion of photo-excited holes in viscous electron fluid

Yu. A. Pusep·M. D. Teodoro·V. Laurindo Jr.·E. R. Cardozo de Oliveira·G. M. Gusev·A. K. Bakarov
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Abstract

The diffusion of photo-generated 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 consisted of electrons and photo-generated 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.

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Yu. A. Pusep, M. D. Teodoro, V. Laurindo Jr., E. R. Cardozo de Oliveira, G. M. Gusev, A. K. Bakarov. 2022-03-31. Diffusion of photo-excited holes in viscous electron fluid. https://doi.org/10.1103/physrevlett.128.136801

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