TY - JOUR A2 - Sun, Fengqiang AU - Augustine, Anju K. AU - Mathew, S. AU - Radhakrishnan, P. AU - Nampoori, V. P. N. AU - Kailasnath, M. PY - 2014 DA - 2014/11/26 TI - Size Dependent Optical Nonlinearity and Optical Limiting Properties of Water Soluble CdSe Quantum Dots SP - 623742 VL - 2014 AB - We present third-order optical nonlinear absorption in CdSe quantum dots (QDs) with particle sizes in the range of 4.16–5.25 nm which has been evaluated by the Z-scan technique. At an excitation irradiance of 0.54 GW/cm2 the CdSe QDs exhibit reverse saturation indicating a clear nonlinear behavior. Nonlinearity increases with particle size in CdSe QDs within the range of our investigations which in turn depends on the optical band gap. The optical limiting threshold of the QDs varies from 0.35 GW/cm2 to 0.57 GW/cm2 which makes CdSe QDs a promising candidate for reverse-saturable absorption based devices at high laser intensities such as optical limiters. SN - 2356-749X UR - https://doi.org/10.1155/2014/623742 DO - 10.1155/2014/623742 JF - Journal of Nanoscience PB - Hindawi Publishing Corporation KW - ER -