Bottom‐Up Fabrication of Photonic Defect Structures in Cholesteric Liquid Crystals Based on Laser‐Assisted Modification of the Helix

Controlled fabrication of defect structures is performed in cholesteric liquid crystals by a laser-assisted polymerization process that induces a local elongation of the helix (see figure). Low-threshold laser action is observed from the photonic defect-mode observed within the selective reflection band.