Ab initio study of structural stability and electronic properties of GeV in diamond

A complete theory is the guide and explanation of the experiment. According to the first principle, the stable structure of Ge vacancy color center (GeV) is the double vacancy center structure by using the constructed GeV color center supercell. The covalent radius and bond angle of GeV are explored by analyzing the microstructures. The electronic structure of GeV color center is calculated, and the charge transfers of GeV color center are explained, thereby demonstrating the existence of stable bonds. The principle of the energy-level transition of the GeV color center in terms of light emission is described. The effect of each element and energy level orbital is illustrated by the density-of-states diagram.

Double cascade dressed MOSFET from doped Eu3+and Pr3+ in a host YPO4

By changing different parameters of single and double lasers, we observed the dressed energy level transition from single to multi-level with a single laser. Each sample responded based on their ions' structure and phase symmetry in the host YPO crystal.

Preparation of Nd:YAG Nanopowders by the Urea Co-Precipitation

Nd:YAG nanopowder was prepared by urea co-precipitation method. XRD, TG-DTA, SEM and spectra analysis were utilized to study the properties of the powder. Results indicated that fine Nd:YAG nanopowder can be acquired at 1000°C for 10h. The fluorescence spectra shown that the strongest peak was located at 1061nm, corresponding to the 4F3/24I11/2 energy level transition of Nd3+ ion.

Synthesis and Light-Emission Properties of Manganese-Doped Calcium Zirconate Phosphor and Manganese-Doped Strontium Zirconate Phosphor

This study successfully synthesized manganese-doped calcium zirconate phosphor and manganese-doped strontium zirconate phosphor using the sol-gel method. We employed X-ray powder diffraction and fluorescence spectroscopy to analyze the crystal structure and spectral characteristics of both phosphors. In X-ray powder diffraction analysis, data related to manganese-doped calcium zirconate phosphor and manganese-doped strontium zirconate phosphor were compared using X-ray diffraction comparison software to confirm the crystal structures of both phosphors. The crystal structure of manganese-doped calcium zirconate phosphor was in accordance with orthorhombic perovskites belonging to the Pnma {62} space group. The lattice parameters were a=5.762 Å, b=8.017 Å, and c=5.591 Å; c/a=0.97; volume=258.3 Å3, and density=4.611 g/cm3. The crystal structure of manganese-doped strontium zirconate phosphor conformed to orthorhombic perovskites belonging to the Pnma {62} space group, and the lattice parameters were a=5.818 Å, b=8.204 Å, c=5.797 Å; c/a=0.996; volume=276.7 Å3, and density=5.446 g/cm3. Fluorescence spectroscopy indicated that the primary broadband peak of manganese-doped calcium zirconate phosphor was located at 396.6 nm in the excitation spectrum corresponding to the 4T2(4G)4T1(4P) energy level transition. In the emission spectrum, the primary broadband peak was located at 596.6 nm, corresponding to the 4T2(4D)4T2(4G) energy level transition. For manganese-doped strontium zirconate phosphor, the primary broadband peak was located at 496.6 nm in the excitation spectrum and at 696.6 nm in the emission spectrum, corresponding to the 4T1(4G)4T2(4D) and 4E(4G)4T1(4G) energy level transitions, respectively.