Cholesteric liquid crystal self-organization of gold nanoparticles

International audience; Self-organization processes are present in many different inorganic, organic, and biological systems at various length scales and give rise to specific intrinsic physical properties. In the present work, we demonstrate the symbiotic association of gold nanoparticles within a cholesteric (chiral) liquid crystal, and we report the long-range growth of two-dimensional and three-dimensional self-organized arrangements of gold nanoparticles into various cholesteric textures. The structure of these novel nanomaterials is imaged at various scales—from the macroscopic scale of centimetre-size cells to the nanoscale of self-assemblies—and we demonstrate that the nanoparticle pattern depends strongly on film thickness. Furthermore, we investigate how fundamental optical properties such as selective reflection are affected when cholesteric liquid crystals are doped with gold nanoparticles. Potential applications are envisioned in the field of soft nanotechnology and optical materials.