Optical Waveguide Based on a Polarized Polydiacetylene Microtube

: An optical waveguide based on a PDA microtube has been prepared through a novel hierarchical assembly method. The waveguide performance of the PDA microtube can be easily modulated upon external stimuli. The polarization of the out-coupled emission light seems independent of the propagation distance, which should be ascribed to the ordered alignment of PDA chains in the microtube.