Fig. 4: Analysis of extinction coefficient and orbital radius.
From: Nonlinearity-induced nanoparticle circumgyration at sub-diffraction scale
a Extinction coefficient \({Q}_{{\rm{ext}}}\) (i.e., extinction cross-section normalized by the geometry cross-section \(\pi {a}^{2}\)) and its enhancement \(\frac{{Q}_{{\rm{ext}}}}{{Q}_{{\rm{ext}},0}}\), where \({Q}_{{\rm{ext}},0}\) is the extinction coefficient without nonlinearity. b Extinction enhancement with different nonlinearities under various particle absorptions for GNPs. c Simulation result of the rotation radius \({r}_{0}\) under various incident power and particle nonlinearity for GNP with a = 30 nm. The light wavelength is 840 nm and NA = 0.65. d The experimental rotation radii of gold and silver particles. In Fig. 4d, the standard deviation bars are included. The different radii at the same power shows they have different nonlinearity.
