A systematic study of the microstructure and laser characteristics of Pr3+-doped lithium lutetium fluoride

Investigation of the Structure and Luminescence Mechanism of Tm3+-Doped LiYF4: New Theoretical Perspectives

“…A similar result can also be found in the LiLuF 4 :Pr 3+ system. 36 Although the radius of the Tm 3+ (0.87 Å) ion is almost equal to that of the Y 3+ (0.89 Å) ion, the impurity Tm 3+ ion causes a crucial structural distortion of the YLF crystal. The lattice constants for YLF:Tm 3+ are tabulated in Table S1.…”

“…32−37 Recently, this method succeeded in properly studying the luminescence mechanisms for lanthanide ions doped into various crystal lattices by incorporating different types of correlation crystal fields, spin−spin interactions and irreducible representa-tions. 35,36 For Tm 3+ ions with a 4f 12 configuration, the model Hamiltonian can be written as 41,42…”

“…By using the Crystal structure AnaLYsis by Particle Swarm Optimization (CALYPSO) − method and the local density approximation (LDA) method based on density functional theory (DFT) in Vienna Ab Initio Simulation Package (VASP), − we successfully identified the lowest-energy structure of YLF:Tm 3+ for the first time. On the basis of our newly developed Well-Established Parametrization Matrix Diagonalization (WEPMD) method, − the Stark energy levels of YLF:Tm 3+ are further accurately calculated for further investigations. Furthermore, some significant dipole transitions of Tm 3+ -doped YLF are discovered, which show potential application in near-infrared lasers.…”

Unveiling the Local Structure and Luminescence Mechanism of Er3+-Doped LiYF4: A Promising Near-Infrared Laser Crystal

“…To obtain the accurate Stark levels of YLF:Er 3+ , our developed WEPMD method was introduced to calculate the energy levels, − and this method has been successfully applied to the systems of lanthanide ions doped into various crystals we studied previously. − For the Er 3+ -doped LiYF 4 system, Er 3+ ions replace Y 3+ ions in sites with the S 4 local symmetry, and the Hamiltonian is given in eqs – where Most of the parameters ( E AVE , F k , ζ nl , α, β, γ, T i , P j , and M n ) in the atomic Hamiltonian were described in our previous study. − The S 4 point symmetry of Er 3+ in YLF can indirectly infer the corresponding nonvanishing parameters of the crystal field (CF) Hamiltonian. In combination with free-ion (FI) parameters, it is worth mentioning that the total number of parameters is 22 for the energy level fitting of Er 3+ -doped LiYF 4 , and only six nonvanishing crystal field parameters (CFP) have to be considered in the S 4 symmetry.…”

The geometrical structure and electronic properties of trivalent Ho3+doped Y2O3crystals: a first-principles study

“…The CALYPSO is a reliable structure prediction method which has been validated by a large variety of crystal structures. [28][29][30][31][32] We perform an evolutionary variable-cell structure prediction with 80 atoms per simulation cell at ambient pressure. To determine the most stable structure of Y 2 O 3 : Ho system, we optimized the all lowest-lying candidate structures by using the density functional theory in VASP (Vienna Ab Initio Simulation Package) code.…”