摘要
报道了纳米银颗粒的局域表面等离子体共振能显著提高全息聚合物分散液晶(H-PDLC)光栅的衍射效率。着重分析了球形纳米银颗粒在PDLC中的表面等离子体共振特性,根据Mie理论,模拟计算了球形纳米银颗粒在PDLC材料中的消光光谱并得出了相应的表面等离子体共振峰值,且该值与用光谱仪测得的材料吸收峰值相近。同时,根据准静态近似理论,模拟了球形纳米银颗粒在特定波长的光照射下的球内外电场分布。证明了球形纳米银颗粒在聚合物分散液晶材料中发生表面等离子体共振,当用与共振峰值相近的激光对材料进行曝光时,可以增强液晶与聚合物的相分离过程,所制备的光栅样品结构更加整齐平滑,从而提高了光栅的衍射效率。
The effect of localized surface plasmon resonance of Ag nanoparticles on the diffraction efficiency of holographic polymer dispersed liquid crystal grating (H-PDLC) is reported. The surface plasmon resonance characteristic of spherical Ag nanoparticles within the PDLC material is analyzed. According to Mie theory, the extinction spectra of spherical Ag nanoparticles surrounded by PDLC material are simulated and then the resonance wavelength is found in the extinction spectra, which is very similar to the resonance wavelength value measured by spectrometer. In addition, the electric field distribution inside and outside the spherical Ag nanoparticles is simulated according to quasi-static approximation method. It is testified that Ag nanoparticles exhibit surface plasmon resonance in the PDLC material during holographic recording process, thus the phase separation between liquid crystal and polymer is significantly improved and the grating structure is much smoother than the sample without Ag nanoparticles, which greatly increases the diffraction efficiency of H- PDLC grating.
出处
《激光与光电子学进展》
CSCD
北大核心
2014年第2期142-147,共6页
Laser & Optoelectronics Progress
基金
国家自然科学基金青年基金(60801041)
上海市研究生创新基金(JWCXSL1202)
上海市人才发展基金(2012026)
上海市教育委员会科研创新项目(14ZZ138)
关键词
材料
表面等离子体共振
纳米银
聚合物分散液晶
全息光栅
materials
surface plasmon resonance
nano-Ag
polymer dispersed liquid crystal
holographic grating