Plasmonic Optical Nonlinearities of Copper Sulfide Nanoparticles
Published online by Cambridge University Press: 22 January 2018
Spherical Cu2-xS nanoparticles with an average diameter of 4.6 nm were synthesized by a colloidal method, and their optical nonlinearities around localized surface plasmon resonance in the near-infrared region were investigated. Resonant enhancement of nonlinear absorption, which is similar to that in the case of the noble metal nanoparticles in the visible region, was observed. The nonlinear absorption coefficients of the Cu2-xS nanoparticles were smaller as compared with those of Au nanoparticles with the same dimensions and concentrations. Theoretical simulation of electric field distributions around individual nanoparticles suggested that the free carrier concentration in Cu2-xS nanoparticles was one order of magnitude smaller than that in Au nanoparticles, which led to a weaker local electric field and weaker optical nonlinearity.
- Copyright © Materials Research Society 2018