A single CW infrared laser beam can simultaneously trap and excite an individual colloidal quantum dot. Though the laser light is relatively weak, the excitation occurs through two-photon absorption. This finding eliminates the demand for an excitation light source in addition to a trapping laser in nanoscale experiments with simultaneous force-manipulation and quantum dot visualization. Also, ...

Colloidal semiconductor quantum dots have three-dimensional confined excitons with large optical oscillator strength and gain. The surface plasmons of metallic nanostructures offer an efficient tool to enhance exciton-exciton coupling and excitation energy transfer at appropriate geometric arrangement. Here, we report plasmon-mediated cooperative emissions of approximately one monolayer of ense...

UNLABELLED We have proposed a method to probe metal to insulator transition in VO2 measuring photoluminescence response of colloidal quantum dots deposited on the VO2 film. In addition to linear luminescence intensity decrease with temperature that is well known for quantum dots, temperature ranges with enhanced photoluminescence changes have been found during phase transition in the oxide. Cor...

We discuss fundamental differences in electronic structure as reflected in one- and two-photon absorption spectra of semiconductor quantum dots and organic molecules by performing systematic experimental and theoretical studies of the size-dependent spectra of colloidal quantum dots. Quantum-chemical and effective-mass calculations are used to model the one- and two-photon absorption spectra an...

Quantum dots are new types of fluorescent materials for biological labeling. As a result, QDs toxicity study is an essential requirement for future clinical applications. Therefore, the cytotoxic CdSe:ZnS quantum dots effects on some organs in mice are presented in this study. In this work, 10, 20 and 40 mg/kg doses of CdSe:ZnS quantum dots were injected to 32 adult male mice. Structural and op...

We propose and demonstrate a nanocomposite localized surface plasmon resonator embedded into an artificial three-dimensional construction. Colloidal semiconductor quantum dots are assembled between layers of metal nanoparticles to create a highly strong plasmon-exciton interaction in the plasmonic cavity. In such a multilayered plasmonic resonator architecture of isotropic CdTe quantum dots, we...

Quantum dots (QDs) are an emerging class of photoactive materials that exhibit extraordinary optical features. This paper presents a review colloidal QD synthesis and the reasons behind their use in light emission applications.

Quantum dots are new types of fluorescent materials for biological labeling. As a result, QDs toxicity study is an essential requirement for future clinical applications. Therefore, the cytotoxic CdSe:ZnS quantum dots effects on some organs in mice are presented in this study. In this work, 10, 20 and 40 mg/kg doses of CdSe:ZnS quantum dots were injected to 32 adult male mice. Structural and op...

Methods for introducing new magnetic, optical, electronic, photophysical, or photochemical properties to semiconductor nanocrystals are attracting intense applications-oriented interest. In this communication, we report the preparation and electronic absorption spectroscopy of colloidal ZnO DMS-QDs. Our synthetic procedure involves modification of literature methods known to yield highly crysta...

Efficient photoluminescence ~PL! up-conversion has been observed in colloidal CdTe quantum dots with an energy gain of as high as 360 meV. Compared with the normal PL, the peak energy of this up-converted PL ~UCPL! shows a redshift of about 80 meV, and the corresponding radiative lifetime becomes nearly twice as long. This UCPL is attributed to the carrier recombination involving surface states...