Υπερταχεία μη γραμμική οπτική απόκριση υψηλών φουλλερενίων και endohedral φουλλερενίων

In this work we present experimental results related to the ultrafast electronic nonlinear optical response of higher fullerenes and their endohedral derivatives. The Optical Kerr Effect technique was employed for the determination of the third order susceptibility ( ) 3 χ and the second order hyperpolarizability γ of these materials. A laser pulse of 830 nm and 100 fs duration was applied for the study of the nonlinearity that the two C84 isomers D2 (IV) and D2d (II) and a C84 isomer mixture exhibit. The same technique was applied to the C82 and C92 cages and the Dy@C82, Dy2@C82 and Er2@C92 endohedral fullerenes, respectively. We determined the values of ( ) 3 χ and γ of those materials and we investigated the influence of the encapsulated metal atoms on the nonlinear optical response of the carbon cages. In addition, measurements were carried out at laser wavelengths of 900 nm and 1000 nm, where no resonant contributions are present as in the case of 830 nm