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arXiv · 0905.1210

Nonequilibrium electrons in tunnel structures under high-voltage injection

N. B. Kopnin·Y. M. Galperin·J. Bergli·V. M. Vinokur
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Abstract

We investigate electronic distributions in nonequilibrium tunnel junctions subject to a high voltage bias $V$ under competing electron-electron and electron-phonon relaxation processes. We derive conditions for reaching quasi-equilibrium and show that, though the distribution can still be thermal for low energies where the rate of the electron-electron relaxation exceeds significantly the electron-phonon relaxation rate, it develops a power-law tail at energies of order of $eV$. In a general case of comparable electron-electron and electron-phonon relaxation rates, this tail leads to emission of high-energy phonons which carry away most of the energy pumped in by the injected current.

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N. B. Kopnin, Y. M. Galperin, J. Bergli, V. M. Vinokur. 2009-05-08. Nonequilibrium electrons in tunnel structures under high-voltage injection. https://doi.org/10.1103/physrevb.80.134502

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