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Johnson-Nyquist noise in films and narrow wires

Misha Turlakov
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Abstract

The Johnson-Nyquist noise in narrow wires having a transverse size smaller than the screening length is shown to be white up to the frequency $D/L^2$ and to decay at higher frequencies as $ω^{-{1/2}}$. In two-dimensional films having a thickness smaller than the screening length, the Johnson-Nyquist noise is predicted to be frequency independent up to the frequency $σ_{2D}/L$ and to have a {\it universal} $1/ω$ spectrum at higher frequencies. These results are contrasted with the conventional noise spectra in neutral and three-dimensional charged liquids.

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Misha Turlakov. 2000-02-10. Johnson-Nyquist noise in films and narrow wires. https://doi.org/10.1103/physrevb.62.4656

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