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arXiv · cond-mat/0212030

Shot-noise in transport and beam experiments

U. Gavish·Y. Levinson·Y. Imry
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Abstract

Consider two Fermi gases with the same {\it average} currents: a transport gas, as in solid-state experiments where the chemical potentials of terminal 1 is $μ+eV$ and of terminal 2 and 3 is $μ$, and a beam, i.e., electrons entering only from terminal 1 having energies between $μ$ and $μ+eV$. By expressing the current noise as a sum over single-particle transitions we show that the temporal current fluctuations are very different: The beam is noisier due to allowed single-particle transitions into empty states below $μ$. Surprisingly, the correlations between terminals 2 and 3 are the same.

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U. Gavish, Y. Levinson, Y. Imry. 2002-12-02. Shot-noise in transport and beam experiments. https://doi.org/10.1103/physrevlett.87.216807

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