Thermal-Equilibrium Properties of Vacancies in Metals through Current-Noise Measurements

Abstract

We report a new method of measuring thermal-equilibrium properties of vacancies in metals through current-noise measurements. Aluminum noise spectra taken at 435 and 475\ifmmode^\circ\else\textdegree\fi{}C directly yield vacancy lifetimes ${\ensuremath{\tau}}_{0}=4.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3} \mathrm{and} 2.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ sec, respectively, corresponding to a migration energy ${E}_{m}=0.6$ eV, and permit estimation of a unit vacancy resistivity $\ensuremath{\Delta}{\ensuremath{\rho}}_{v}=1.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}$ \ensuremath{\Omega}m/at.% from the measured product ${(\ensuremath{\Delta}{\ensuremath{\rho}}_{v})}^{2}{\ensuremath{\eta}}_{v}$, ${\ensuremath{\eta}}_{v}$ being the vacancy concentration taken from literature data.