A Layered-Composite Nanometric Sb2Te3 Material for Chiral Photonic Bandgap Engineering

Biological systems have been using nanometre-scale architectures to produce striking optical effects and the way these natural photonic structures manipulate the flow of light has inspired many technological applications. Nevertheless, the applications of these natural structures in photonic devices require appropriate fabrication techniques able to tailor and enhance the natural features of the biological systems. In this communication the authors report on the development of a layered-composite nanometric Sb2Te3 material for the realization of bio-inspired three-dimensional chiral photonic crystals exceeding their natural optical properties. The authors demonstrate that the deposition of Sb2Te3 on laser written polymer templates can fabricate biomimetic photonic structures with superior control over size, periodicity, filling fraction, and refractive index, compared with the natural counterparts. In this way the refractive index of the photonic crystals can be increased by 100% and the photonic bandgap for use in practical devices can be precisely engineered. These bio-inspired structures can be useful in the investigation of new branches of photonics and in the development of novel chiral optical devices capable of manipulating photons in three dimensions.