Reflectance measurements of triangular lattice GaAs nanowire arrays

Triangular lattice GaAs nanowires were fabricated using electron beam lithography defined Au arrays and metalorganic vapour phase epitaxy. Reflectance measurements for GaAs NW arrays with varying pitch in a triangular lattice are presented. The measured spectra are compared to the literature data on square lattice NW arrays and selective-area epitaxy grown triangular lattice NW arrays. Reflectance from a triangular lattice NW array is found to have similar characteristics as from a square lattice. Unlike for the square lattice, it is observed that the reflection edge does not depend linearly on the NW diameter with smallest pitches in the triangular lattice and that a Morse potential fit describes the behaviour most closely.