Intrinsic single crystals were deformed, under hydrostatic pressures, at temperatures down to 130K. The slip-lines indicated that, below 300K, deformation occurred via ½<10¯1>{111} slip with frequent cross-slip. At temperatures above 300K, the crystal was so brittle that no slip-lines were observed, and the critical resolved shear stress fell steeply with increasing temperature. At temperatures below 300K, the temperature dependence of the critical resolved shear stress was weak, and resulted in a hump in the critical resolved shear stress versus temperature curve at about 300K (like that in InP at 420K). In this region, the activation volume was equal to several times b3; where b was the length of the Burgers vector. The activation energy was equal to about 35kT. Transmission electron microscopy of specimens which were deformed at low temperatures revealed long screw dislocations which were narrowly, or not at all, dissociated. Semi-quantitative analyses indicated that, at low temperatures, plastic deformation occurred via kink-pair formation of non-dissociated shuffle screw dislocations.

Plastic Deformation of GaAs at Low Temperatures T.Suzuki, T.Yasutomi, T.Tokuoka, I.Yonenaga: Philosophical Magazine A, 1999, 79[11], 2637-54