Figure 2: Initial plasticity of Au [110] nanowires by prismatic loops.

(a) Low-magnification TEM image of the compression setup using a flat diamond punch. Scale bar, 500 nm. (b) TEM DF image showing the initial compressive deformation accommodated by the nucleation of prismatic loops (white arrows) and half-loop shaped dislocations (yellow arrows). Upon emission, these loops slip along the glide planes lying parallel to the loading axis, that is, (a) and (b) planes in Fig. 1d. The loops spacing remained in the range of ~50–100 nm, and the dislocation density was measured to be on the order of ~10⁹–10¹⁰ cm⁻². Scale bar, 100 nm. (c) TEM DF images of open prismatic dislocation loops recorded at various two-beam conditions. The dislocations are visible in the first two images recorded at g=200 and g=020. In the last image recorded at g=, the dislocations are invisible. According to the g·b invisibility criterion, the Burgers vector is determined as a/2. The weak residual contrast of the dislocations remained at g= originates from the g·b × u contrast, refer to Methods for details. Scale bar, 100 nm.