高双折射球霰石微球：制备、表征及光镊应用

Highly birefringent vaterite microspheres: production, characterization and applications for optical micromanipulation.

作者信息

Parkin Simon J, Vogel Robert, Persson Martin, Funk Maren, Loke Vincent L Y, Nieminen Timo A, Heckenberg Norman R, Rubinsztein-Dunlop Halina

机构信息

University of Queensland, School of Mathematics and Physics, Queensland, Australia.

出版信息

Opt Express. 2009 Nov 23;17(24):21944-55. doi: 10.1364/OE.17.021944.

DOI:10.1364/OE.17.021944

PMID:19997439

Abstract

This paper reports on a simple synthesis and characterization of highly birefringent vaterite microspheres, which are composed of 20-30 nm sized nanocrystalls. Scanning electron microscopy shows a quite disordered assembly of nanocrystals within the microspheres. However, using optical tweezers, the effective birefringence of the microspheres was measured to be Deltan = 0.06, which compares to Deltan = 0.1 of vaterite single crystals. This suggests a very high orientation of the nanocrystals within the microspheres. A hyperbolic model of the direction of the optical axis throughout the vaterite spherulite best fits the experimental data. Results from polarized light microscopy further confirm the hyperbolic model.

摘要

本文报道了由20 - 30纳米大小的纳米晶体组成的高双折射球霰石微球的简单合成与表征。扫描电子显微镜显示微球内纳米晶体的组装相当无序。然而，使用光镊测量微球的有效双折射为Δn = 0.06，而球霰石单晶的Δn = 0.1。这表明微球内纳米晶体的取向非常高。整个球霰石球粒光轴方向的双曲线模型最符合实验数据。偏光显微镜的结果进一步证实了双曲线模型。