Understanding and resolving the mechanisms that affect the photoluminescence (PL) of Si QDs are of great importance because of their strong potential for optoelectronic and solar cell materials. In this article, the intrinsic exciton dynamics of water-dispersed allylamine-functionalized silicon quantum dots (Si QDs) have been explored as a function of temperature by means of steady-state and ti...

A comprehensive investigation of a chromium-doped near-infrared fluoride phosphor with desired anti-thermal quenching behavior.

We have examined state filling and thermal activation of carriers in buried InAs self-assembled quantum dots sSAQDsd with excitation-dependent cathodoluminescence sCLd imaging and spectroscopy. The InAs SAQDs were formed during molecular-beam epitaxial growth of InAs on undoped planar GaAs s001d. The intensities of the groundand excited-state transitions were analyzed as a function of temperatu...

We have examined the optical properties of self-assembled InAs quantum dots ~QDs! with polarization sensitive and time-resolved cathodoluminescence ~CL! techniques. The InAs QDs were formed via self-assembly during molecular beam epitaxial growth of InAs on unpatterned GaAs~001!. CL spectra exhibited a two-component line shape whose linewidth, intensity, and peak positions were found to be temp...

The surface chemistry of upconversion nanoparticles can effectively control the quenching effect water molecules affecting thermal dynamics luminescence.

The fluorescence rise kinetics in saturating light display two well separated com ponents with largely different properties. The rapid rise from F„ to a first intermediate level, I ,, is photochemically controlled, while the following phases leading to a secondary intermediate level, I2, and to a peak level, P , are limited by thermal reactions. Treatm ents which primarily affect components at ...

A method to image near-surface hardness profiles of heat-treated case-hardened steels using laser infrared photothermal radiometric phase imaging is described. It is shown that thermophysical and mechanical transverse inhomogeneity profiles in industrial case hardened steel samples are well correlated. Phase surface scanning imaging leads to a practical criterion for assessing transverse hardne...

We report the fabrication and operation of a Cr:ZnSe buried channel waveguide laser operating at 2500 nm with a linewidth of 10 nm and a maximum power output of 1.7 W. Ultrafast laser inscription is used to fabricate the depressed cladding waveguide in a polycrystalline Cr:ZnSe sample. A thermal model is developed and predicts performance degradation at higher pump levels due to thermal quenchi...

Stimulated gluon emission and thermal absorption, in addition to induced radiation, are considered for an energetic parton propagating inside a quark-gluon plasma. In the presence of thermal gluons, stimulated emission reduces, while absorption increases, the parton's energy. The net effect is a reduction of the parton energy loss. Though decreasing asymptotically as T/E with the parton energy,...