Paper presents the comparative investigation of photoluminescence and Raman scattering spectra of pure amorphous silicon films and amorphous silicon films with different size Si nanocrystallites. Several PL bands in the IR spectral range with maxima at 0.90, 0.98, 1.14 and 1.36 eV have been revealed in studied samples. The 0.90–0.98 eV PL bands are attributed to the band tail luminescence in Si...

This paper reports experimental study on the development of cadmium tungstate scintillator material in the form of nanocrystal films through controlled sol–gel processing and pre-designed doping. We chose cadmium tungstate as a base material for doping and nanostructure development due to its excellent inherent photoluminescence (PL) property, and chemical and thermal stability including non-hy...

We studied the local optical response of semiconducting single-walled carbon nanotubes to wrapping by DNA segments using high resolution tip-enhanced near-field microscopy. Photoluminescence (PL) near-field images of single nanotubes reveal large DNA-wrapping-induced red shifts of the exciton energy that are two times higher than indicated by spatially averaging confocal microscopy. Near-field ...

Microstructural and optical properties of InAs-inserted and reference single GaAsN/GaAs quantum-well ~QW! structures grown by metalorganic chemical vapor deposition were investigated using cross-sectional transmission electron microscopy and photoluminescence ~PL!. Significant enhancement of PL intensity and a blueshift of PL emission were observed from the InAs-inserted GaAsN/GaAs QW structure...

The GaAs surface passivation effects of epitaxially grown ultra-thin GaP layers and surface As–P exchange have been investigated. Optical properties of passivated and unpassivated InGaAs/GaAs near-surface quantum wells (QWs) grown by metal organic vapor phase epitaxy (MOVPE) are studied by low-temperature continuous-wave and time-resolved photoluminescence (PL). By optimizing the growth conditi...

The photoluminescence (PL) spectrum of KBr0.95 I0.05:Eu 2+ (0.05mol %) mixed crystal gives emission of europium at 420nm. This 420nm emission is due to the transition from T 2g component of 4f 6 5d configuration to the ground state 8s of europium. When adding Tl + ion as co-activator in KBr0.95 I0.05:Eu 2+ (0.05mol %) mixed crystal the same PL emission observed and enhanced their PL intensity. ...

A detailed analysis of the strong room-temperature photoluminescence ~PL! signal of size controlled nc-Si is reported. The size control of nc-Si is realized by evaporation of SiO/SiO2 superlattices and subsequent thermally induced phase separation. By this method the synthesis of completely SiO2 passivated Si nanocrystals with a controlled size is demonstrated. A strong blueshift of the photolu...

The photoluminescence (PL) properties of the Cu:Zn-In-S core quantum dots (QDs) and core-shell QDs were systematically investigated by using steady-state and time-resolved PL spectra at temperatures ranging from 80 to 400 K. The effects of the shell structure and the host bandgap on the thermal stability of Cu dopant emissions were studied by measuring the change in the PL intensity and the lif...

External electric field effects on spectra and decay of photoluminescence (PL) as well as on absorption spectra were measured for CdSe nanoparticles in a poly(methyl methacrylate) (PMMA) film. Electrophotoluminescence (E-PL) spectra as well as electroabsorption spectra show a remarkable Stark shift which depends on the particle size, indicating a large electric dipole moment in the first excito...

Nanocrystalline Zinc Oxide (ZnO) powders with different morphology have been successfully synthesized by using different surfactants such as Cetyl Trimethyl Ammonium Bromide (CTAB), Sodium Dodecyl Sulphate (SDS), and Tri Ethanol Amine (TEA) via hydrothermal method. The products were characterized by means of powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electr...