Optical nonlinearity or the nonlinear hyperpolarizability of amorphous materials (e.g., glasses) is related directly to the complex third-order susceptibility. The imaginary part of third-order susceptibility affects negatively the maximum data rate in telecommunication systems. In addition, many transition metals containing glasses have bandgaps with semiconductor-like behavior. So, due to the necessity of operation near the absorption band edge, the study of optical nonlinearity and band structure in glasses is very essential. In this work, we investigated the relationship between the imaginary third-order nonlinear susceptibility and the bandgap of some different series of prepared oxide glasses. A universal empirical formula is given to correlate the imaginary part of the third-order nonlinear susceptibility of the glasses and their optical bandgaps. The obtained nonlinearity is discussed in view of available theories and mechanisms.
© 2009 Optical Society of America
Original Manuscript: December 18, 2008
Revised Manuscript: January 14, 2009
Manuscript Accepted: February 25, 2009
Published: April 23, 2009
Fouad El-Diasty, Manal Abdel-Baki, and Assem M. Bakry, "Resonant-type third-order optical nonlinearity and optical bandgap in multicomponent oxide glasses," Appl. Opt. 48, 2444-2449 (2009)