Folding photonic crystals : Semiconductors ORIGAMI – PHOLDING

Selective etching of pre-stressed multi-layered structures enables to release intrinsic stresses creating flexible macroscopic shapes (rolls, spirals, tubes…). By combining stress-engineering and photonic concepts, PHOLDING project propose to develop a numerical and experimental methodology to obtain complex three-dimensional photonic structures, by folding a two-dimensional photonic crystal membrane, in controlling material composition, mask design and etching process. This project targets specifically the generation of new families of 3D hollow optical micro-resonators, with the peculiar properties of enabling a strong trapping and enhancement of light in a low index media. Light confinement is achieved by enclosing a small region of space with the folded photonic membrane designed to present a broad-band and high reflectivity in the wavelength range of interest. This leads to the achievement of very open resonators where strong light-matter interaction can be exploited in optical devices comprising an active material embedded in a low index matrix like polymer, liquid or even gas.