Electron relaxation in disordered gold films

Abstract

The analysis of quantum corrections to magnetoconductivity of thin Au films responsible for by the effect of weak electron localization has made it possible to determine the temperature dependences of electron phase relaxation time in the temperature range 0.5--50 K for different degrees of crystal lattice disorder. The disorder was enhanced by irradiating the films in vacuum with 3.5 keV Ar ions. The experimental data clearly demonstrate that the contribution of electron-electron interaction to electron phase relaxation increases with disorder and support the theoretical prediction that the frequency of electron-phonon scattering tends to diminish upon a decrease in electron mean free path. It is found that the spin-orbit scattering rate decreases with disorder. In our opinion, such unusual behavior can take place for thin films at decreasing the electron mean free path provided, that the surface electron scattering contributes significantly to the total spin-orbit scattering.Comment: 15 pages, REVTex, 6 Postscript figures, To be published in Phys. Rev.

Mixed 1D-2D quantum electron transport in percolating gold film

“…5), that corresponds to p = 2.1. This agrees with results for disordered but homogeneous enough gold films [11], where this has been convincingly attributed to influence of electron-phonon phase relaxation.…”

“…Generally, the phase relaxation is determined by the two main contributions: electronelectron and electron-phonon interactions, so that τ −1 in = τ −1 ee + τ −1 ep , where τ ee and τ ep are the corresponding times. It was found for the electron-phonon interaction processes in disordered (R up to ≈ 500 Ω) gold films that τ −1 ep ∝ T p with exponent p between 2 and 2.8 [11]. According to Ref.…”

“…It is known that gold is characterized by strong spin-orbit interaction [τ so ≪ τ in (T )], which determines specific value of a T , and causes appearance of positive magnetoresistance due to the WL effect [4], as it is usually observed in gold films (Refs. [8,11] and Refs. therein), including the film studied (see Fig.…”

Electron relaxation in metals: Theory and exact analytical solutions

“…The exponent n depends on impurities, disorder, and sample dimensions: n = 2 in clean bulk crystals, while n =1 in disordered metals due to a phonon damping 30,31 and in metallic films. 32 Then Eq. ͑31͒ can be Fourier transformed into the Schrödinger equation using Fourier transform equation ͑13͒ of ͑ , t͒ϵ͑ , t͒cosh͑ / 2͒.…”

Two-Dimensional Superconducting State of Monolayer Pb Films Grown on GaAs(110) in a Strong Parallel Magnetic Field

“…In Ref. [24], the probability of the spin-orbit process on elastic (momentum) scattering was determined for defect scattering in 10-nm-thick Au films after irradiation of Ar ions. From weak localization magnetoresistance measurements, the ratio of τ to be 3.1 and 3.5 fs for n = 9.4 and 11.3 nm −2 , respectively [25].…”