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Shot-noise suppression by Fermi and Coulomb correlations in ballistic conductors

O. M. Bulashenko·J. M. Rubi
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Abstract

We investigate the injection of degenerate Fermi-Dirac electrons into a multimode ballistic conductor under the space-charge limited regime. The nonequilibrium current fluctuations were found to be suppressed by both Coulomb and Fermi correlations. We show that the Fermi shot-noise suppression factor is limited below by the value 2kT/epsilon_F, where T is the temperature and epsilon_F the Fermi energy of the injected electrons. The Coulomb noise suppression factor may attain much lower values epsilon_F/2qU, because of its dependence on the applied bias U >> kT/q. The asymptotic behaviour of the overall shot-noise suppression factor in a high degenerate limit was found to be kT/qU, independently of the material parameters.

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O. M. Bulashenko, J. M. Rubi. 2001-08-22. Shot-noise suppression by Fermi and Coulomb correlations in ballistic conductors. https://doi.org/10.1103/physrevb.64.045307

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