Quantum size effects on the third order optical nonlinearity of CdS quantum dots in Nafion

• Published in: Optics communications Vol. 185; no. 4; pp. 457 - 465
• Main Authors: Nandakumar, P., Vijayan, C., Murti, Y.V.G.S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.11.2000; Elsevier Science
• Subjects: Exact sciences and technology; Fundamental areas of phenomenology (including applications); Nonlinear optics; Optical materials; Optical phase conjugation; Optical susceptibility, hyperpolarizability; Optics; Other nonlinear optical materials; photorefractive and semiconductor materials; Phase conjugation, optical mixing, and photorefractive effect; Phase conjugation, optical mixing; photorefractive and kerr effects; Physics; Semiconductor quantum dots; Third order susceptibility; 42.70.N; Semiconductor quantum dots; 42.65; Optical phase conjugation; 78.66; Third order susceptibility; 42.65.H; Semiconductor materials; Four-wave mixing; Quantum dots; Cadmium sulfides; Binary compounds; Experimental study; Nonlinear optics; Optical susceptibility; Phase conjugation
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/S0030-4018(00)01009-9

Optical nonlinearities of CdS quantum dots in the strongly confined regime are probed through degenerate four-wave-mixing experiments in an attempt to study the size dependence of the third order optical susceptibility χ (3). The results indicate that χ (3) is strongly dependent on the diameter of the dots and that there is a large increase in χ (3) values as the diameter decreases below 2 nm. Polarization discrimination studies point to nonthermal contributions to the mechanism of optical nonlinearity.