2019年论文发表
发布时间：2020-04-25
点击次数：
Our paper "An ultranarrow photonic nanojet formed by an engineered two-layer microcylinder of high refractive-index materials" by Zhishen Zhen, Yin Huang*, Yuanhua Feng, Yuecheng Shen*, and Zhaohui Li, is accepted in Optics express.
Abstract: photonic nanojet (PNJ) is a tightly focused beam that appears onto the shadow surface of microparticles. Due to its high peak intensity and subwavelength beam waist, the PNJ has increasingly attracted attention, with potential applications in optical imaging, nanolithography, and nanoparticle sensing. A variety of ways have been demonstrated to further shrink the beam waist of PNJs, such as engineering the microparticle geometry and optimizing a multilayer structure. In this simulation work, we report the realization of an ultranarrow PNJ, which is formed by an engineered two-layer microcylinder of high refractive-index materials. Finite element analysis shows that under 632.8 nm illumination, the full width at half maximum of the beam waist can reach 87 nm (~λ/7.3). As far as we know, this is the narrowest PNJ ever reported. Using the backscattering intensity as a contrast mechanism, we also demonstrated the imaging resolution and capability of this ultranarrow PNJ. We anticipate that this ultranarrow PNJ will open new possibilities in a variety of research areas, including nanoparticle detection, biomedical imaging, and nanolithography.
