title: Broadband reflection in polymer stabilized cholesteric liquid crystal films with stepwise photo-polymerization.
abstract: In this study, we demonstrate a novel method for fabricating polymer stabilized cholesteric liquid crystal (PSCLC) films with non-uniform pitch distribution by utilizing two kinds of photo-induced processes. Based on the large HTP temperature dependence of a chiral dopant, polymer networks were formed at two distant temperature points in sequence. The influence of the polymerization conditions on the reflectance properties of PSCLCs before and after polymerization was investigated. The results strongly suggest that the location and bandwidth of the reflection band can be controlled preferably by adjusting the ultraviolet light intensity and irradiation time of UV-light. In addition, the morphology of the polymer network in the composites was studied using scanning electron microscopy (SEM). A general correlation between polymerization conditions, the network morphology, and the reflective region will be outlined.
authors.affiliation: State Key Laboratory for Advanced Metals and Materials, Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China. caohui@mater.ustb.edu.cn.
authors.forename: Man-Yu
authors.initials: MY
authors.lastname: Duan
authors.affiliation: State Key Laboratory for Advanced Metals and Materials, Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China. caohui@mater.ustb.edu.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Cao
authors.affiliation: State Key Laboratory for Advanced Metals and Materials, Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China. caohui@mater.ustb.edu.cn.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory for Advanced Metals and Materials, Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China. caohui@mater.ustb.edu.cn.
authors.forename: Er-Li
authors.initials: EL
authors.lastname: Li
authors.affiliation: Center for Nanochemistry (CNC), College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
authors.forename: Hui-Hui
authors.initials: HH
authors.lastname: Wang
authors.affiliation: State Key Laboratory for Advanced Metals and Materials, Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China. caohui@mater.ustb.edu.cn.
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.affiliation: State Key Laboratory for Advanced Metals and Materials, Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China. caohui@mater.ustb.edu.cn.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Yang
authors.affiliation: State Key Laboratory for Advanced Metals and Materials, Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China. caohui@mater.ustb.edu.cn.
authors.forename: Wan-Li
authors.identifier: http://orcid.org/0000-0002-2803-0602
authors.initials: WL
authors.lastname: He
authors.affiliation: Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing, 100871, P. R. China.
authors.forename: Huai
authors.initials: H
authors.lastname: Yang