向列相和蓝相液晶随机激光的等离激元调控与泵光调控研究

In order to study the disordered photonics and realize the application prospects of random lasers, the property manipulation of the random lasers has become one of the central issues of the random lasing research field. The project focuses on the plasmonic control and pump-light control of the liquid crystal random lasers.In this project we will study the optical properties of the metalline nanoparticles in the liquid crystal matrix and the effects of the orientatin of the liquid crystal on the localized surface plasmonic resonance of the metal nanoparticles.We will study the excitation and coupling mechanism of the localized surface plasmons of metal nano particles and explore the influence of the localized surface plasmonic resonance of metal nanoparticles on the output peroperties of the liquid crystal random lasers.We wll also study how to use the adjustment of the gain and the absorption to realize the plasmonic control of the nematic liquid crystal random lasers and the polymer dispersed liquid crystal random lasers.We will study the control of the emission properties and the excitation threshold of the liquid crystal and polymer dispersed liquid crystal random lasers, implemented by the wavefron shaping of the pump beam and the partial pumping,and We will study the operating mechnism and the emission properties of the blue phase liquid crystal(BPLC) random lasers and try to demonstrate the switching and manipulation from the BPLC band-edge lasing to the BPLC random lasing.The research of the project not only have deep physical meanings,but have potencial application prospect in the future photonic integration and flatpanel display as well. Implementation of the project has important scintific significances for the nano-photonics,subwavelength liquid crystal optics,random lasers and related theory & application research.

为了研究随机介质光子学和实现随机激光的应用远景，随机激光的性能调控已成为当今随机激光研究领域的中心议题。本项目计划围绕液晶随机激光等离激元调控和泵光调控开展下述研究工作：(1)研究液晶环境下金属纳米颗粒的光学特性和液晶取向对金属纳米颗粒局域表面等离激元共振的影响。（2）研究液晶环境下金属纳米颗粒表面等离激元的激发和耦合机制，探讨金属纳米颗粒表面等离激元共振对液晶随机激光输出特性的影响。（3）研究利用表面等离激元共振对增益和吸收的调节实现向列相液晶和聚合物分散液晶随机激光的等离激元调控。(4)研究利用泵浦光的波面调节和部分泵浦实现对液晶随机激光发射特性和阈值特性的调控。（5）研究蓝相液晶随机激光的发射特性和工作机制，实现蓝相液晶光子带边激光和随机激光的转换与调控。本项目研究不仅具有深刻的物理内涵，而且具有重要的应用前景，对于纳米光子学、液晶光物理、随机激光理论和应用的研究具有重要的科学意义。

对随机激光的性能进行有效调控是实现随机激光应用的关键之一。 本项目围绕向列相液晶和蓝相液晶随机激光的等离激元调控和泵光调控问题，开展了下述研究工作：（1）研究了各向异性液晶环境下金属纳米颗粒的光学特性和液晶分子取向变化对金属纳米颗粒表面等离激元共振的影响。（2）研究了液晶环境下金属纳米颗粒表面等离激元共振的激发和耦合机制，探讨了金属纳米颗粒表面等离激元共振对掺杂液晶随机激光输出特性和激射阈值的影响。（3）利用金属纳米颗粒-液晶复合物随机激光样品中吸收和增益的调节，研究并实现了金属纳米颗粒介入的向列型液晶和聚合物分散液晶随机激光的等离激元调控。（4）利用泵浦光的调节和部分泵浦，实现了向列相液晶液晶随机激光发射特性和阈值特性的调控。（5）研究了蓝相液晶随机激光的发射特性和工作机制，研究了蓝相液晶光子带边激光和随机激光之间的转换，首次实现了染料掺杂聚合物稳定蓝相液晶双色随机激光的输出及其泵浦光偏振调控。（6）通过调整随机激光样品的掺杂浓度、在样品内添加贵金属纳米颗粒、寻找可替代的半导体材料（如氮化钛等）等方式来设计激光样品，我们实现了向列相液晶随机激光的模式、阈值、强度、波长和稳定性等的调控。本项目研究成果对于未来基于液晶随机激光的低成本光子器件的制作和平板显示应用研究具有重要的意义。