Effects of the surface coating and of the size on the nonlinear optical response of magnetic iron oxide nanoparticles

In this work, new results are presented concerning the nonlinear optical properties of some recently synthesized magnetic iron oxide nanoparticles (MIONs) coated with sodium carboxy-methylcellulose (abbreviated as NaCMC) and having various sizes ranging from 7 nm to 20 nm. The present work is part of ongoing research aiming to investigate the influence of nanoparticles´ surface coating and the effect of morphological parameters such as nanoparticles´ size, geometry etc. on their nonlinear optical response. The nonlinear absorption and refraction and the third-order nonlinear susceptibility χ⁽³⁾ of NaCMC coated MIONs have been studied by means of the Z-scan technique employing visible (532 nm) and infrared (1064 nm), 35 ps laser pulses. The present results are compared with previously obtained results concerning similar MIONs coated with another polyelectrolyte namely poly(sodium4-styrenesulfonate) (abbreviated as NaPSS).