基于纳米三角板自组装体系的可调控多势阱表面等离激元光镊及其应用研究

光镊是一种利用光场中的光学梯度力势阱来实现对微粒捕获与操纵的技术，传统光镊由于受到衍射极限和高功率激光的限制，无法操控纳米级别的粒子。表面等离激元是金属表面自由电子与外部电磁场相互作用形成的一种表面电磁模式。由于表面等离激元(SPP)具有局部场增强效应，可将激发的电磁场能量局域在突破衍射极限的亚波长尺度内，故可构成光势阱并实现对纳米级别粒子的捕获和操纵。本项目提出构建基于金属纳米三角板且光场可控的表面等离激元光镊系统，选用低经济成本、低时间成本、尺度不受限制甚至可模板化的金属纳米三角板自组装薄膜，通过可逆控制材料参量并结合光场的光学参量，可获得具有特定光场分布且具备可操控性的光镊系统，同时具备在生物、环境及相关研究领域更广泛的应用潜力。此外，该系统与传统光镊系统相比可突破衍射极限，与物理刻蚀的纳米结构相比具有制备方面的明显优势，与纳米颗粒或纳米棒相比，纳米三角板也具有更强的光场局域特性。

Optical tweezers are capable of trapping and manipulating particles by using optical gradient force in light fields.As traditional optical traps are confined by the diffraction limit and high power lasers, it cannot trap and control the nanoscale particles. Surface plasmon polaritons (SPP) are tightly confined electromagnetic waves that propagating along a metal-dielectric interface arising from the coupling of light with collective oscillations of electrons. Due to their significant field enhancement and subwavelength field confinement, SPPs have the potential to form optical traps to capture and manipulate nanoparticles. In this project, a surface plasmon optical tweezers system based on metal nanoprisms and controllable optical field is proposed. It is with low economic cost, low time cost, unrestricted scale and even templatable..By controlling the material parameters reversibly and combining with the optical parameters of the light field, the optical tweezer system can be with specific light field distribution and controllability which has a wider applications in biological, environmental and related research fields. In addition, the system can break through the diffraction limit compared with traditional optical tweezers, has obvious advantages in preparation compared with physical etching nanostructures, and has stronger light field localization characteristics compared with nanoparticles or nanorods etc..