Robust determination of the anisotropic polarizability of nanoparticles using coherent confocal microscopy

US8045161B2 · kind B2 · utility

Assignee

• The Board of Trustees of the University of Illinois · US

Inventors

• Brynmor J. Davis · Champaign, US
• Paul Scott Carney · Champaign, US

Key dates

• Filing date: Mar 17, 2009
• Grant date: Oct 25, 2011
• Expiry date: Mar 12, 2030

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/4792
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A coherent confocal microscope for fully characterizing the elastic scattering properties of a nanoparticle as a function of wavelength. Using a high numerical aperture lens, two-dimensional scanning and a simple vector beam shaper, the rank-2 polarizability tensor is estimated from a single confocal image. A computationally efficient data processing method is described and numerical simulations show that this algorithm is robust to noise and uncertainty in the focal plane position. The measurement of the polarizability removes the need for a priori assumptions regarding the nanoparticle shape.