Bioinspired photonic nanoarchitectures from graphitic thin films

Bioinspired, regular, rectangular (with periodicities of 600 nm and 700 nm), and random (with average characteristic distances of 600 nm and 750 nm) two dimensional (2D) photonic nanoarchitectures of 60 nm thickness were produced in graphite by Focused Ion Beam (FIB) nanomachining and subsequent controlled oxidation. The color of the nanoarchitectures was modified by the conformal deposition of 90 nm Al2O3. The regular patterns generate iridescent colors, while the random ones exhibit a remarkably constant color with the variation of the illumination and viewing conditions.