Fig. 1. (a) Experimental setup, laser interference system with the laser and the optical elements to guide the beams; (b) resulting line like structure on a sample (from [3] and [9]).

Fig. 2. Target preparation by focused ion beam: (a) milling process imaged in SEM mode; (b) prepared TEM foil imaged in STEM mode with a total thickness of 50 nm and a thinner area of 20 nm for high resolution imaging. The foil shows two laser interference maxima (zone 1) separating by a laser interference minimum (zone 2) to analyze the periodical microstructure.

Fig. 3. Cross-sectional TEM image on a laser interference maximum: (a) bright field with dark Ni and bright Al sublayers; (b) dark field. The microstructure in the individual Al sublayers appears to be fine grained in the area 2 (5–10 nm), one large grain in the area 3 (>100 nm), and unchanged nano-grained structure in the rest of the sample named area 1 (20–30 nm).

Fig. 4. TEM diffraction images: (a) un-irradiated layers without ordered intermetallics’ reflexes and a strong fiber texture (Fig. 3b area 1); (b) strongly irradiated layers with ordered intermetallics’ reflexes and a texture change with an orientation spread (Fig. 3b area 2); (c) one weakly irradiated and laterally grown Al grain (Fig. 3b area 3).

Fig. 5. Lattice plane images: (a) interface between Ni (left upper corner) and Al (right bottom corner) in the fifth Al layer, the interface is semi-coherent; (b) grain structure in the second Al layer with its nano-crystalline structure.