Related papers: Luminescence of alpha-quartz
Photoluminescence and thermally stimulated luminescence of synthetic and natural (morion and smoky) $\alpha$-quartz crystals doped with aluminum and alkali ions were studied. The photoluminescence spectrum is characterized with the main…
The optical properties of point defects in as-grown natural silica are reviewed. Two emissions peaked at 4.2 eV ($\alpha_E$ band) and at 3.1 eV ($\beta$ band), related to an absorption band at 5.1 eV ($B_{2\beta}$), have been experimentally…
Luminescence characteristics of single crystals (SC), single crystalline films (SCF), powders and ceramics of YAlO_3 and YAlO_3:Ce have been studied at 4.2-300 K under photoexcitation in the 4-20 eV energy range and X-ray excitation. The…
Using STIS and VLT UVES observations we have examined the ionization, abundances, and differential dust depletion of metals, the kinematic structure, and the physical conditions in the molecular hydrogen-bearing sub-damped Ly alpha system…
Caesium iodide is one of the more extensively studied scintillators. Here we present X-ray luminescence spectra, scintillation light output and decay curves as function of temperature, from room temperature down to below 10 K. Features of…
The photo-luminescence features of Ge-oxygen defect centers in a 100nm thick Ge-doped silica film on a pure silica substrate were investigated by looking at the emission spectra and time decay detected under synchrotron radiation excitation…
Applications that utilize scintillation detectors at low temperatures are growing in number. Many of these require materials with high light yield and a fast response. Here we report on the low-temperature characterisation of ZnSe doped…
Temperature behavior of the Bi+ center emission, excitation bands and luminescence decay law in KAlCl4 crystal are investigated. Abrupt changes of the monocation optical properties are observed at phase transitions of the host. The observed…
An electron spin resonance (ESR) and photoluminescence signal is observed in the as grown single crystal of stishovite indicating the presence of defects in the non-irradiated sample. Photoluminescence of the as received stishovite single…
The photoluminescence (PL) spectra of Ar-ion irradiated single crystals of SrTiO3 (STO) excited by the 325 nm line of a He-Cd laser are compared with those of pristine crystals, epitaxial films, and amorphous layers of STO at several…
The spectral--kinetic characteristics of a ZnO:Ga single crystal upon excitation in the vacuum UV region have been studied. At a temperature of 8 K, the exciton luminescence line peaking at 3.356 eV has an extremely small half-width (7.2…
Nanostructured semiconductors emit light from electronic states known as excitons[1]. According to Hund's rules[2], the lowest energy exciton in organic materials should be a poorly emitting triplet state. Analogously, the lowest exciton…
We have conducted temperature dependent Angle Resolved Photoemission Spectroscopy (ARPES) study of the electronic structures of PbTe, PbSe and PbS. Our ARPES data provide direct evidence for the \emph{light} hole upper valence bands (UVBs)…
The temperature-dependent electronic structures of heavy fermion compound CeB$_{6}$ are investigated thoroughly by means of the combination of density functional theory and single-site dynamical mean-field theory. The band structure,…
Luminescence spectra of NiO have been investigated under vacuum ultraviolet (VUV) and soft X-ray (XUV) excitation. Photoluminescence (PL) spectra show broad emission bands centered at about 2.3 and 3.2 eV. The PL excitation (PLE) spectral…
Two-dimensional (2D) perovskite materials have recently re-attracted intense research interest for applications in photovoltaics and optoelectronics. As a consequence of the dielectric and quantum confinement effect, they show strongly…
Near band gap photoluminescence (PL) of hBN single crystal has been studied at cryogenic temperatures with synchrotron radiation excitation. The PL signal is dominated by the D-series previously assigned to excitons trapped on structural…
The peak effect (PE) has been observed in a twinned crystal of YBa$_2$Cu$_3$O$_{7-\delta}$ for H$\parallel$c in the low field range, close to the zero field superconducting transition temperature (T$_c$(0)) . A sharp depinning transition…
An atomically flat interface is achieved between face-centered cubic Al and diamond lattice Ge via molecular beam epitaxy (MBE). Based on the measurements of scanning tunneling microscopy (STM), we demonstrate an atomically resolved lateral…
The organic metal \theta$-(BETS)$_4$HgBr$_4$(C$_6$H$_5$Cl) is known to undergo a phase transition as the temperature is lowered down to about 240 K. X-ray data obtained at 200 K indicate a corresponding modification of the crystal…