Second-harmonic generation in a novel crosslinked pyroelectric liquid crystal polymer (PLCP)

• Published in: Liquid crystals Vol. 24; no. 2; pp. 295 - 310
• Main Authors: HERMANN, D. S., RUDQUIST, P., LAGERWALL, S. T., KOMITOV, L., STEBLER, B., LINDGREN, M., TROLLSAS, M., SAHLEN, F., HULT, A., GEDDE, U. W., ORRENIUS, C., NORIN, T.
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01-02-1998
• ISSN: 0267-8292; 1366-5855
• DOI: 10.1080/026782998207479

We report second-harmonic generation in samples with a pyroelectric liquid crystal polymer (PLCP) prepared from the ferroelectric liquid crystalline acrylate monomer 4-[(R)-(-)-2-(10-acryloyloxydecyl)oxy]-3-nitrophenyl 4-[4-(11-acryloyloxyundecyloxy)phenyl]- benzoate (A2c) by in situ photopolymerization. The relation between SHG efficiency, spontaneous polarization and amount of chiral substance in this and previously synthesized PLCP materials is discussed. Electro-optical properties of the monomeric and crosslinked A2c are investigated. In the crosslinked state, the molecular mobility is found to be very low, supporting the fact that the degree of polar order in the polymer is high. In contrast to the case of a poled electret NLO material, the polarization of this material is not 'frozen-in', but an intrinsic thermodynamic property.