Electron dislocation drag at low temperatures

Abstract

Dislocationdefect dragging in electronirradiated copper over the temperature range 4.2-350°KMeasurements of the influence of a magnetic field on the stress of plastic deformation for a number of materials are presented. These measurements are given for copper, some copper alloys, zinc, cadmium, lead, and bismuth. The measurements, carried out at a number of temperatures between 1.8 and 40 K, show that this change in stress has a monotonic and an oscillatory dependence upon the magnetic field. The oscillatory dependence on field has a temperature dependence which is consistent with a lIT 3 dependence. We also show that the oscillations are strain rate dependent as well as strain dependent. These results are compared with the inertial model of dislocation motion and the agreement is quite good. Measurements of the orientation dependence of the magneto-oscillations allows us to assess the relative velocities of screw and edge dislocations, showing that, at low temperatures, screw dislocation move faster than do edge dislocations. Agreement is also found between the present measurements of the Fermi surface extrema and acoustic measurements. Finally the temperature where the dislocations no longer act as underdamped oscillators is compared with theory.3747

The mechanics and physics of high-speed dislocations: a critical review

“…Moreover, as we discuss below, phonon scattering due to lattice anharmonicities is amenable to theoretical studies accounting the effect high speed dislocations. The effect of electron drag has also been estimated through indirect experimental evidence [135,[463][464][465].…”