浸没于液体中钛酸钡微球（n>2）的纳米成像-中国材料进展

文章信息/Info

作者:: 李文新1; 周佩珩1; 邓龙江1; 洪明辉2; （1. 电子科技大学国家电磁辐射控制材料工程技术研究中心，四川成都 611731）（2. 新加坡国立大学电子与计算机工程系，新加坡市 117576）

Author(s):: LI Wenxin1; ZHOU Peiheng1; DENG Longjiang1; HONG Minghui2; （1.National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu 611731, China) （2.Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore)

Keywords:: BTG microsphere; nano-imaging; immersion; microsphere assisted microscope; virtual image

摘要:: 由于光学衍射极限的存在，传统的光学显微镜不能分辨特征尺寸小于衍射极限的微小特征，使用范围受限，许多研究工作者在如何打破衍射极限，提高光学显微镜效率方面做了大量的研究。其中，利用光学玻璃微球可以辅助传统光学显微镜分辨小于光学衍射极限的微小特征。本研究将高折射率(n~2.2)BaTiO3玻璃(BTG)微球浸没在不同折射率的液体中用来辅助传统光学显微镜，以实现纳米成像。在波长为405 nm的入射光照射下，可以很清晰地观察到蓝光光盘样品100 nm宽的纳米特征尺寸；通过调整玻璃微球与周围介质折射率对比度可以优化纳米成像的质量，将BTG微球浸没于折射率为1.46的液体中，得到的虚像质量最好。这种高折射率微球的纳米成像技术在纳米光子学、生物医学和流体领域有着广泛的应用前景。

Abstract:: Due to the existence of optical diffraction limit, the traditional optical microscope can not distinguish the tiny features smaller than the diffraction limit. And, its application scope is limited. Many researchers have conducted a lot of studies on how to break the diffraction limit and improve the efficiency of optical microscope. Among them, the optical glass microsphere can assist the traditional optical microscope to distinguish the tiny features smaller than the optical diffraction limit. In this work, high refractive index (n~2.2) BaTiO3 glass microspheres (BTG, diameter=28 μm) immersed inside liquids with different refractive indices are used to achieve nano-imaging. It provides a route to improve the property of optical microscope. A blue disk sample with a feature size down to 100 nm can be clearly observed under an incident light with wavelength of 405 nm. The nano-imaging quality and contrast can be optimized by tuning the microsphere-medium refractive index contrast. When the BTG microsphere is immersed inside the liquid with the refractive index of 1.46, the contrast of virtual image is the best. This nano-imaging of high refractive index microsphere can be widely applied in nano-photonics, biomedicine and fluid fields.