An investigation is reported of the photoluminescence (PL) properties of Al3GdB4O12:Eu phosphors. Under vacuum ultraviolet excitation, Al3GdB4O12:Eu exhibited a bright red luminescence with CIE chromaticity coordinates of (0.643, 0.356) with a PL intensity of 60% of the sodium salicylate standard. The PL spectrum showed a ground state splitting pattern consistent with D3 symmetry. The PL excita...

We report infrared photocurrent ~PC! and photoluminescence ~PL! spectroscopy of self-assembled Ge dots grown on Si~100! by molecular beam epitaxy. PL spectra show a transition from twoto three-dimensional growth as the Ge thickness exceeds 7 Å. The sum of the PC peak energy and PL energy from Ge dots is found to be approximately equal to the energy band gap of Si. Boron doping changes the energ...

C60 molecules were chemically coupled in the pores of porous Si through a coupling agent and then coated with a layer of Si, and followed by N2 annealing. X-ray diffraction results indicate that the fabricated samples contain b-SiC particles which may exist in the pores, in addition to Si, SiO2, and graphite. The photoluminescence ~PL! spectra show an asymmetrical broadband, which can be Gaussi...

Cadmium chalcogenides with appropriate band gap energy have been attracting a great deal of attention because of their potential applications in optoelectronic devices. In this work CdS thin films were deposited on p – type silicon substrates by sol – gel spin coating method at different substrate temperatures. The CdS deposited wafers were characterized by X‐ray diffracti...

Photoluminescence ~PL! spectra of partially oxidized porous Si ~POPS! coated with Si thin films were examined using the 488 nm line of Ar laser. The obtained PL is stable, peaks at 1.763 eV with a blueshift of ;60 meV, and its maximal intensity is seven times larger than that of the POPS. Spectral analysis and the experimental results from infrared spectroscopy and electron spin resonance sugge...

The time resolution of scintillation detectors of ionizing radiation is one of the key parameters sought for in the current and future high-energy physics experiments. This study is encouraged by the necessity to find novel detection methods enabling a sub-10-ps time resolution in scintillation detectors and is focused on the exploitation of fast luminescence rise front. Time-resolved photolumi...

Single crystalline zinc oxide (ZnO) nanowires have been grown on Si (100) substrates by a vapor-liquid-solid (VLS) process at temperatures in the range 850-950 °C in an inert atmosphere. The VLS-grown ZnO nanowires have been characterized in detail using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), transmission electron mi...

We present the results of optical studies of the properties of InxGa12xN epitaxial layers (0,x ,0.2) grown by metalorganic chemical vapor deposition. The effects of alloying on the fundamental band gap of InxGa12xN were investigated using a variety of spectroscopic techniques. The fundamental band-gap energies of the InxGa12xN alloys were determined using photomodulation spectroscopy measuremen...

CdTe quantum dots coated with a silica layer containing CdS-like clusters exhibit intense photoluminescence and a spectral red-shift. Biexciton Auger recombination of these particles is examined by transient absorption spectroscopy. A lengthening of the Auger recombination lifetime by a factor of ∼3.5 in the presence of the CdS-like clusters is observed and may contribute to the good PL propert...

In this research Calcium fluoride nanoparticles and its different amount of cerium ion dopant (5%and 10%) were prepared. The mentioned nanoparticle were studied by fourier transform infrared spectroscopy (FTIR) , X-ray diffraction (XRD), absorption and photoluminescence spectra (PL) and Scanning electron microscopy (SEM). The XRD patterns indicate a typical cubic fluorite structure and no other...