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arXiv · 1001.5201

Electron-avalanche amplifier based on the electronic Venturi effect

D. Taubert·G. J. Schinner·H. P. Tranitz·W. Wegscheider·C. Tomaras·S. Kehrein·S. Ludwig
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Abstract

Scattering of otherwise ballistic electrons far from equilibrium is investigated in a cold two-dimensional electron system. The interaction between excited electrons and the degenerate Fermi liquid induces a positive charge in a nanoscale region which would be negatively charged for diffusive transport at local thermal equilibrium. In a three-terminal device we observe avalanche amplification of electrical current, resulting in a situation comparable to the Venturi effect in hydrodynamics. Numerical calculations using a random phase approximation are in agreement with our data and suggest Coulomb interaction as the dominant scattering mechanism.

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D. Taubert, G. J. Schinner, H. P. Tranitz, W. Wegscheider, C. Tomaras, S. Kehrein, S. Ludwig. 2010-10-26. Electron-avalanche amplifier based on the electronic Venturi effect. https://doi.org/10.1103/physrevb.82.161416

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