We have studied by electrical and optical methods the properties of the defects to possibly identify which ones affect the luminescence of the material. We have characterized Er-doped Si samples grown by the Liquid Phase Epitaxy (LPE) method, a relatively simple and inexpensive technique, by means of photoluminescence (PL), cathodoluminescence, EXAFS and deep level transient spectroscopy. The o...

New low-temperature methods to produce GaN:Eu and Ga2O3 :Eu (0 x 1) highly-luminescent powders are presented. These procedures yield finely divided powders through exothermic reactions between the precursors. The preparation of Eu-doped Ga2O3 powders was achieved using a new combustion synthesis technique (hydrazine/metal-nitrate method). The process starts with aqueous solutions of Eu(NO3)3 an...

We propose an array of submicrometer mirrors to assess luminescent nano-objects. Micromirror arrays (MMAs) are fabricated on Si (001) wafers via selectively doping Ga using the focused ion beam technique to form p-type etch stop regions, subsequent anisotropic chemical etching, and Al deposition. MMAs provide two benefits: reflection of luminescence from nano-objects within MMAs toward the Si (...

A new concept of luminescent host-guest materials was developed by introduction of Eu(3+) into COK-16, a HKUST-1 type hybrid metal-organic framework (MOF) with cation exchange properties. In Eu@COK-16, the luminescent ion resides in the pore system of the MOF. The luminescence properties of Eu@COK-16 have been studied based on excitation and emission, allowing analysis of intramolecular energy-...

GaAs/AlGaAs quantum wells ~QWs!, selectively disordered using an AlAs native oxide and thermal annealing technique, were studied using spectrally, spatially, and temporally resolved cathodoluminescence ~CL!. The spectral shift of the QW luminescence was determined as a function of annealing temperature in the oxide and nonoxide regions. Time-resolved CL was used to assess the impact of defects ...

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...

We present a systematic, temperature-dependent study of excitonic real-space transfer into single GaAs quantum wires using time-resolved low-temperature near-field luminescence spectroscopy. Excitons generated by local short pulse optical excitation in a 250 nm spot undergo diffusive transport over a length of several micrometres and are subsequently trapped into the quantum wire by optical pho...

Two europium complexes with bis(bipyridine) azamacrocyclic ligands featuring pendant arms with or without π-conjugated donor groups are synthesized and fully characterized by theoretical calculations and NMR spectroscopy. Their photophysical properties, including two-photon absorption, are investigated in water and in various organic solvents. The nonfunctionalized ligand gives highly water-sta...

Luminescence spectroscopy is a vitally important technique for characterising the defects present in diamond. In this paper the two major methods for generating the emission photoluminescence and cathodoluminescence are considered, and the defects responsible for the most significant luminescence bands are discussed in detail. Problems with the donor acceptor pair model, conventionally used to ...

The chainlike silicon nanowires SiNWs have been synthesized by fluctuating the pressure of the carrier gas in the growth process. The chainlike SiNWs comprise crystalline Si nanoparticles interconnected by amorphous silicon oxide wires. In addition to the sphere, other interesting shapes such as rectangular and triangular Si nanoparticles in chainlike SiNWs were also observed. X-ray absorption ...