Ultrasonic determination of electron-phonon scattering rates in copper

Electron-phonon scattering rates in ultrapure single crystals of copper have been determined from the temperature dependence of the magnetoacoustic oscillation amplitudes for various orbits on the Fermi surface using both longitudinal and transverse waves. The central belly orbit seattering rate is found to be (6.0±0.3)×10⁶T³ sec^–1. Additionally, a rate of (2.9±0.2)×10⁶T³ sec^–1 is found which is attributed to belly orbits displaced from the zone center by about 1.25/a₀, wherea₀ is the lattice constant. Geometric oscillations associated with the [111]—directed open orbit are observed at low fields forq [113] and the rate for this orbit is found to be (4.8±0.3)×10⁶T³ sec^–1. Geometric oscillations for the dog's bone and neck orbits are observable but rates for these orbits are believed to be unreliable. Our measured rates are compared with those of other workers.