The T-matrix method, or the T-matrix formulation of scattering, is a framework for mathematically describing the scattering properties of an object as a linear relationship between expansion coefficients of the incident and scattering fields in a basis of vector spherical wave functions (VSWFs). A variety of methods can be used to calculate the T-matrix. We explore the applicability of the extended boundary condition method (EBCM) and point matching (PM) method to calculate the T-matrix for scattering by cylinders in optical tweezers and hence the optical force acting on them. We compare both methods with the discrete-dipole approximation (DDA) to measure their accuracy for different sizes and aspect ratios (ARs) for Rayleigh and wavelength-size cylinders. We determine range of sizes and ARs giving errors below 1% and 10%. These results can help researchers choose the most efficient method to calculate the T-matrix for nonspherical particles with acceptable accuracy.
© 2014 Optical Society of America
Original Manuscript: May 2, 2014
Revised Manuscript: July 1, 2014
Manuscript Accepted: July 3, 2014
Published: August 12, 2014
Vol. 9, Iss. 10 Virtual Journal for Biomedical Optics
Xiaoqiong Qi, Timo A. Nieminen, Alexander B. Stilgoe, Vincent L. Y. Loke, and Halina Rubinsztein-Dunlop, "Comparison of T-matrix calculation methods for scattering by cylinders in optical tweezers," Opt. Lett. 39, 4827-4830 (2014)