Size Dependent Optical Nonlinearity and Optical Limiting Properties of Water Soluble CdSe Quantum Dots

Abstract

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 -scan technique. At an excitation irradiance of 0.54 GW/cm 2 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/cm 2 to 0.57 GW/cm 2 which makes CdSe QDs a promising candidate for reverse-saturable absorption based devices at high laser intensities such as optical limiters.

Nonlinear Optical Properties of CdSe and CdTe Core-Shell Quantum Dots and Their Applications

“…For calculating the 1s-1s electronic transition in spherically layered semiconductor quantum dots extended theoretical approach was introduced by A. Eychmüller et al [167]. Venkatram et al reported that CdSe nanoparticles of different sizes show multiphoton absorption under 800 nm excitation [168]. The particle size ranging from 4.16 to 5.25 nm of CdSe QDs exhibits reverse saturable absorption under 532 nm laser excitation and the two-photon absorption (TPA) coefficient values enhance when decreasing the bandgap [137].…”

Liquid Crystal Systems with WS2 Nanoparticles in the Optical Limiting Effect

“…Результаты экспериментов по оптическому ограничению для системы ЖК-WS 2 наночастицы приведены на рис. 1, а также в сравнительной таблице [10,[16][17][18][19][20][21][22][23][24][25][26][27][28].…”

Tunneling-induced optical limiting in quantum dot molecules

“…It is well-known that the transitions between different electronic states in QD nanostructures can be optically excited by laser fields. In this context, studying nonlinear optical process, including RSA and saturable absorption (SA) have been pursued by several researchers [29][30][31][32] ; for example, the intensity-dependent nonlinear absorption and nonlinear refraction of QDs were experimentally investigated in Ref. 29 .…”