Policryps structure for color-tunable organic micro-cavity laser

Polymer-liquid-crystal-polymer-slides (POLICRYPS) is a new structure made of polymer stripes alternated to pure liquid crystal films. It is obtained by photo-curing of a liquid crystal and monomer mixture: The sample is acted on by a UV interference pattern and, due to the diffusion of liquid crystal and monomer molecules, an inhomogeneous mass transfer effect takes place. Under particular experimental conditions, the process leads to the formation of the POLICRYPS structure. If a dye-doped helixed liquid crystal is used to be embedded within the periodic, polymeric micro-channels, the helical superstructure of the liquid crystal turns out to be oriented along the micro-channels; when the sample is irradiated by coherent light, a lasing effect is observed along the channel direction, at the red-edge of the stop band induced by the helix periodicity. Several physical and technological advantages arise from this micro-cavity laser: high quality factor of the cavity, ultra-slow lasing threshold, thermal and electric control of the lasing wavelength and emission intensity, respectively.