CM In the literature: open

Does the Dutta-Horn fluctuator model describe 1/f noise in metal films?

In plain words

One standard explanation says 1/f noise comes from many defects that hop over energy barriers of different heights. It predicts a fixed link between how the noise spectrum bends and how the noise changes with temperature, and whether real metal films obey it quantitatively is not settled.

Precise statement

In the Dutta-Horn model $S(f, T)$ is a superposition of Lorentzians from thermally activated fluctuators with rates $\left(1/\tau_0\right) \exp(-E/T)$ and a smooth activation-energy distribution $D(E)$; it predicts $\alpha(f, T) = 1 - (d \ln S/d \ln T - 1)/\ln(2 \pi f \tau_0)$, where $\alpha = -d \ln S/d \ln f$. For thin metal films (for example Au, Cu, Ag, Bi) over $f \sim 1e-3 \text{ to } 1e3\,\mathrm{Hz}$ and $T \sim 10 \text{ to } 500\,\mathrm{K}$, determine whether this relation holds with a single $\tau_0$, and whether $D(E)$ inferred from the noise matches $D(E)$ obtained independently (from internal friction or defect spectroscopy).

What would settle it

Noise spectra over at least six decades of $f$ at many temperatures on one film, with the fluctuator energy distribution measured independently, testing the predicted relation with $\tau_0$ as the only parameter.

Related problems

See also