Local electrooptic effect of the SiC large-sized nanocrystallites incorporated in polymer matrices

Linear electro-optical effect (LEO) is experimentally demonstrated in large-sized (10 and 30 nm) silicon carbide nanocrystallites (nc-SiC) incorporated in poly(N-vinylcarbazole) (PVK) blended with coumarine (MK). By using the angle-dependent polarimetric method a lambda(probe) = 694 nm, in both static and photoinduced regimes, we have shown that embedding the nc-SiC within polymer host matrices gives rise to an enhancement of the LEO effective parameters up to 1.325 pm/V. The absence of these phenomena in the separate components-i.e., pure wurtzite-like SiC crystals as well as the organic matrices-suggests that the observed local electro-optical response is intimately driven by the interfacial hyperpolarizabilities appearing between the nc-SiC and the surrounding organic matrix. (C) 2002 Elsevier Science B.V. All rights reserved.