Extended Data Fig. 1: Analysis of the pure Al sample.
From: On the origin of diffuse intensities in fcc electron diffraction patterns
Transmission electron microscopy images (a, c, d) and SADP (b) taken from the pure aluminum sample. The grain highlighted in the Bright Field image taken down the [111] zone axis in (a) was analyzed in the region indicated by the yellow circle, the scale bar is 1 micron. The sample was then tilted to a two-beam condition for the 422 planes, and oriented to the Bragg condition of the \({}^{1}{ / }_{3}\){422} extra reflection as shown in (b). The arrows denote the location of the intensities at the \({}^{1}{ / }_{3}\) and \({}^{2}{ / }_{3}\) positions and the line denotes where the “Kikuchi line” of the extra intensity would be if observable. A BF(b)/DF(c) pair of images was then acquired from the highlighted region in (a) using the \({}^{1}{ / }_{3}\){422} extra reflection. A long exposure time (of about 90 s) was used for the DF image. Note that no defects (e.g., stacking faults or dislocations) can be seen in the image inside of the highlighted grain. Furthermore, in the DF image no specific contrast suggesting SRO regions is observed. The scale bar in (c,d) is 300 nm.
