Conductance fluctuations and 1/fnoise in Bi

The 1/f resistance noise of Bi films has been measured as a function of temperature and magnetic field over the ranges 0.3–300 K and 0–8 T, respectively. As the temperature decreases below 70 K, the noise increases, and at 1 K it is larger than at room temperature. Below 20 K the noise magnitude is reduced by a factor of 2 in the presence of a perpendicular magnetic field of magnitude ${\mathrm{\Phi }}_0$/${\mathit{L}}_{\mathrm{\phi }}^2$, where ${\mathrm{\Phi }}_0$ is the flux quantum, and ${\mathit{L}}_{\mathrm{\phi }}$ is the phase-breaking length. These phenomena show that below about 70 K the noise is enhanced by the interference of the conduction electrons on the scale of ${\mathit{L}}_{\mathrm{\phi }}$, as described by Feng, Lee, and Stone.