Open AccessRandom lasing in blue phase liquid crystals
Author(s) -
Chun-Wei Chen,
Hung Chang Jau,
Chun-Ta Wang,
Chun Hong Lee,
Iam Choon Khoo,
TsungHsien Lin
Publication year - 2012
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.023978
Subject(s) - lasing threshold , materials science , random laser , optics , isotropy , liquid crystal , phase (matter) , gain switching , laser , wavelength , optoelectronics , scattering , physics , quantum mechanics
Random lasing actions have been observed in optically isotropic pure blue-phase and polymer-stabilized blue-phase liquid crystals containing laser dyes. Scattering, interferences and recurrent multiple scatterings arising from disordered platelet texture as well as index mismatch between polymer and mesogen in these materials provide the optical feedbacks for lasing action. In polymer stabilized blue-phase liquid crystals, coherent random lasing could occur in the ordered blue phase with an extended temperature interval as well as in the isotropic liquid state. The dependence of lasing wavelength range, mode characteristics, excitation threshold and other pertinent properties on temperature and detailed make-up of the crystals platelets were obtained. Specifically, lasing wavelengths and mode-stability were found to be determined by platelet size, which can be set by controlling the cooling rate; lasing thresholds and emission spectrum are highly dependent on, and therefore can be tuned by temperature.