The F center is the prototype of the excess electron color centers. Although many of the properties of this center are well understood, some interesting questions still remain concerning the nature of its relaxed excited state. The influence of uniaxial stress upon the luminescences has yielded new evidence for the diffuse nature of this state. A contrast will be made of the influence of uniaxi...

The optical properties of sulforhodamine B (SRB) hosted in surfactant-modified layered double hydroxide (LDH) are explored using quantum yield efficiencies and temporal variations luminescence. effect the spacer,...

This paper presents the results of the research on the luminescence of cadmium sulfide nanocrystals (NCs) synthesized by colloid chemistry in a gelatinous matrix. The photostimulation of the short-wavelength emission band with λmax = 480 nm has been detected. It is shown that the determining factor of the photostimulation effect is the adsorption of the water molecules on the surface of NC. The...

We present a model of size-dependent luminescence from a-Si:H and show that a blueshift of the luminescence energy and a general increase in luminescence quantum efficiency are predicted as structure size decreases. In contrast to bulk a-Si:H structures, highly confined a-Si:H exhibits visible luminescence peak energies and high radiative quantum efficiency at room temperature, which is insensi...

This work presents an experimental study on the dislocation luminescence in GaN by nanoindentation, cathodoluminescence, and Raman. The dislocation luminescence peaking at 3.12 eV exhibits a series of special properties in the cathodoluminescence measurements, and it completely disappears after annealing at 500°C. Raman spectroscopy shows evidence for existence of vacancies in the indented regi...

Fingerprints and trace explosives detection requires great sensitivity, which is provided by luminescence and appropriate physical and chemical treatments. Ninhydrin, 1,2-indanedione and other chemicals react with the amino acids present in the fingerprint residue. The chemically treated samples, on which the prints are to be detected, are excited with the blue lines 476.5 and 488 nm of an Argo...

The luminescence of rac-[Ru(bpy)2(dppz)](2+) (bpy = 2,2'-bipyridine and dppz = dipyrido[3,2-a:2',3'-c]phenazine) was explored in the presence of RNA oligonucleotides containing a single RNA mismatch (CA and GG) in order to develop a probe for RNA mismatches. While there is minimal luminescence of [Ru(bpy)2(dppz)](2+) in the presence of matched RNA due to weak binding, the luminescence is signif...

For several decades, energy-transfer upconversion (ETU) in rare-earth-ion doped systems [1,2] has attracted much attention, firstly, because of the fundamental interest in the physical nature of this process and, secondly, because of very practical considerations, namely the demonstration of near-infrared pumped visible light sources and, in reverse, the detrimental influence of ETU on the effi...

We report that nanoscale carbon particles (carbon dots) upon simple surface passivation are strongly photoluminescent in both solution and the solid state. The luminescence emission of the carbon dots is stable against photobleaching, and there is no blinking effect. These strongly emissive carbon dots may find applications similar to or beyond those of their widely pursued silicon counterparts.

By combining upconversion nanoparticles (UCNPs) with rhodamine 6G (R6G) dye molecules, multicolor emission based on energy transfer is achieved. The complexes can be dissolved in epoxy resin, and self-assembled hemispherical microstructures are fabricated through a hydrophobic effect. A luminescence temperature sensor takes advantage of the high temperature sensitivity of the complexes due to e...