Open AccessHighly birefringent vaterite microspheres: production, characterization and applications for optical micromanipulation
Author(s) -
Simon J. Parkin,
Robert Vogel,
Michael Persson,
Maren Funk,
Vincent L. Y. Loke,
Timo A. Nieminen,
N. R. Heckenberg,
Halina RubinszteinDunlop
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.021944
Subject(s) - vaterite , birefringence , materials science , optical tweezers , optical microscope , spherulite (polymer physics) , optics , scanning electron microscope , microsphere , characterization (materials science) , polarized light microscopy , microscopy , nanotechnology , composite material , calcium carbonate , chemical engineering , aragonite , polymer , physics , engineering
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.