CAJ | 학술논문

研究了一种Ag/SiO2/Ag组成的三角形纳米柱的LSPR消光光谱特性及其传感特性.时域有限差分(FDTD)法计算结果表明,三棱柱结构在中间夹层SiO2后,消光光谱峰值出现红移现象,并伴随着折射率灵敏度的增加.随着中间介质层厚度的增加,上下两层金属间表面等离子体耦合逐渐减弱,消光光谱峰值红移速度减慢.当介质层厚度为60 nm时,金属层间的表面等离子体耦合消失,消光光谱与折射率灵敏度不再发生变化.对于实际制作时可能出现尖角钝化的三棱柱结构,中间介质层仍然表现出对其光学及传感特性的良好的调节作用.
연구료일충Ag/SiO2/Ag조성적삼각형납미주적LSPR소광광보특성급기전감특성.시역유한차분(FDTD)법계산결과표명,삼릉주결구재중간협층SiO2후,소광광보봉치출현홍이현상,병반수착절사솔령민도적증가.수착중간개질층후도적증가,상하량층금속간표면등리자체우합축점감약,소광광보봉치홍이속도감만.당개질층후도위60 nm시,금속층간적표면등리자체우합소실,소광광보여절사솔령민도불재발생변화.대우실제제작시가능출현첨각둔화적삼릉주결구,중간개질층잉연표현출대기광학급전감특성적량호적조절작용.
A type of Ag/SiO2/Ag triangular nanoprism was presented and its optical properties and sensing performance were investigated. The calculation results by finite difference time domain (FDTD) numerical method show that the peak wavelength of the extinction spectra with various dielectric thicknesses has remarkable redshift compared with single-material-composed nanoprism, and the refractive index sensitivity increases. When the thickness of SiO2 dielectric layer increases, the plasmon coupling between the top and the bottom silver layers becomes weaker and the redshift speed becomes slower. When the thickness of SiO2 reaches 60 nm, the coupling disappeared;the extinction spectra and refractive index sensitivity are immovable. For the nanoprisms with truncated vertices in experiment, SiO2 dielectric layer also shows good adjustments to its optical properties and sensing performance.