Related papers: Defect physics in $Yb^{3+}$-doped $CaF_2$ from fir…
Defect engineering can improve the linked charge, spin, and lattice behavior of thermoelectric topological insulators. Using density functional theory with spin orbit coupling, we study structural, electronic, optical, thermoelectric,…
Luminescence quenching via non-radiative recombination channels limits the efficiency of optical materials such as phosphors and scintillators and therefore has implications for conversion efficiency and device lifetimes. In materials such…
We report single crystal growth and physical properties characterization of YbFe$_2$Al$_{10}$ compounds. The measurements of resistivity, magnetic susceptibility, and specific heat show different behaviors from previous studies on…
Defects influence the properties and functionality of all crystalline materials. For instance, point defects participate in electronic (e.g. carrier generation and recombination) and optical (e.g. absorption and emission) processes critical…
We demonstrate a direct measurement of the energy levels of impurity-trapped excitons in CaF$_2$:Yb$^{2+}$. The radically different radiative decay rates of the lowest exciton state and higher excited states enable the generation of a…
We report systematic studies of structural, microstructural and transport properties of Y1-xCaxBa2Cu3O7-d bulk samples with 0.20 x 0.0. The partial substitution of Ca2+ at Y3+ site in YBa2Cu3O7-d leads towards slightly overdoped regime,…
Illumination has been long known to affect semiconductor defect properties during either growth or operating process. Current theories of studying the illumination effects on defects usually have the assumption of unaffected formation…
The photoluminescence properties of Yb doped Y2O3 nanoparticles are investigated in visible region. The presence of peaks at 335 nm and 370 nm in the excitation spectra of bulk as well as in nano Yb: Y2O3 and their absence in pure Y2O3…
Ytterbium (Yb) doped fiber lasers are known to be affected by the creation of color centers during lasing (socalled photodarkening (PD)). In a previous work, this defect creation was investigated from a spectroscopic point of view, showing…
Fiber fuse effect can occur spontaneously and propagate along optical fibers to cause wide-spread damage; it threatens all applications involving optical fibers. This paper presents two results. First, it establishes that the initiation of…
We show that charge doping can induce transitions between three distinct adsorbate phases in hydrogenated and fluorinated graphene. By combining ab initio, approximate density functional theory and tight binding calculations we identify a…
First single crystal fibers of cerium doped strontium yttrate are fabricated using the laser-heated pedestal growth technique. Through thermodynamic equilibrium calculations and by high-temperature mass spectrometry suitable growth…
Defect pyrochlore oxides have attracted a great interest as promising luminescent materials due to their flexible composition and high electron/hole mobility. In this work, we investigate the structural and electronic properties of…
Advanced theoretical investigations are crucial for understanding the structural growth mechanisms, optoelectronic properties, and photocatalytic activity of photoelectrodes for efficient photoelectrochemical water splitting. In this work,…
Optimally doped cuprate superconductors are characterized by the presence of superconducting fluctuations in a relatively large temperature region above the critical transition temperature. We reveal here that the effect of thermal…
The Q-factor of superconducting accelerating cavities can be substantially improved by a special heat treatment under N2 atmosphere (N-doping). Recent experiments at Fermi National Laboratory investigated the dependence of Q on the RF…
A comprehensive study of the effects of carbohydrate doping on the superconductivity of MgB2 has been conducted. In accordance with the dual reaction model, more carbon substitution is achieved at lower sintering temperature. As the…
Taking advantages of the broad emission bands of a Yb3+ doped calcium yttrium oxoborate (Yb:YCOB) crystal cut along the optimized direction out of principle planes with the maximum effective nonlinear coefficient, the self-frequency-doubled…
Resonant optical excitation of apical oxygen vibrational modes in the normal state of underdoped YBa2Cu3O6+x induces a transient state with optical properties similar to those of the equilibrium superconducting state. Amongst these, a…
To explore the origin of the unusual non-bulk superconductivity with a Tc up to 49 K reported in the rare-earth-doped CaFe2As2 , the chemical composition, magnetization, specific heat, resistivity, and annealing effect are systematically…