Ultrasonic determination of electron-phonon scattering rates in copper

Electron-phonon scattering rates in noble metals from magnetoacoustic experiments

“…4 Both the magnitude and anisotropy of the coeMcient a for the latter metal are in reasonable agreement with theoretical calculations of the relevant electron-phonon scattering, s Magnetoacoustic experiments on ultrapure single crystals have also been used to analyze the carrier scattering rates in copper. 6 Although the data are consistent with electron-phonon scattering being the dominant process, the coefficients of the T 3 term differ markedly from those obtained from RFSE experiments. For longitudinal waves propagating along [001] with magnetic field along [100], the coefficient a corresponding to a (100) central belly orbit appears to be (6.0+ 0.3)• 106 sec -1 K -3 compared with the value (3.1+ 0.1)• 10 6 sec -1 K -3 obtained from RFSE data.…”

Temperature Dependence of Carrier Scattering Rate in Copper from Magnetoacoustic Experiments

“…4 it can be seen that the approximation corresponding to equation (3 impurities, the two curves become indistinguishable over the entire range of we shown in the graph. Clearly the use of equation 3in analysing the temperature dependence of low-order oscillations will produce a lower effective scattering rate compared with the limiting value, in apparent agreement with experiment (Peverley 1975). However, the detailed calculations shown in Fig.…”

“…2 it can be seen that for harmonic number n > 15 the data are well represented by v(T) = aT 3 , corresponding to catastrophic electron-phonon scattering as in the case of RFSE experiments. Even for n as low as 10 there is no evidence for the T 5 dependence, characteristic of diffusive type scattering, reported by Khatri and Peverley (1975). Fig.…”

“…Fig. 3 shows the corresponding values of a = v(T)/T 3 as a function of harmonic number, using the relevant values of We for copper (Koch et al 1964). For n greater than ~20 the data clearly reach an asymptotic value of a = (2, 7 ± O• 1) x 10 6 S -1 K -3.…”

“…Recent magnetoacoustic experiments (Khatri and Peverley 1975) on ultrapure single crystals have also been used to analyse the carrier scattering rates in copper. Although the data are consistent with electron-phonon scattering being the dominant process, the coefficients of the T3 term differ markedly from those obtained from RFSE experiments.…”