PredictionNet: a long short-term memory-based attention network for atmospheric turbulence prediction in adaptive optics.

Adaptive optics (AO) has great applications in many fields and has attracted wide attention from researchers. However, both traditional and deep learning-based AO methods have inherent time delay caused by wavefront sensors and controllers, leading to the inability to truly achieve real-time atmospheric turbulence correction. Hence, future turbulent wavefront prediction plays a particularly important role in AO.

Ab initio calculation of electronic structure and 4f-5d transition energies of Ce3+ doped in Y3Al5O12 nanocrystals.

The elementary-state electronic structure and 4f-5d transitions of Y3Al5O12:Ce3+ nanocrystals simulated by several clusters were computed by the ab initio self-consistent relativistic DV-X alpha (discrete variational X alpha) method. A 35-ion cluster was chosen to simulate the local surroundings of Ce3+ doped in Y3Al5O12 bulk crystals while four additional smaller irregular clusters were also chosen to simulate the local surroundings of Ce3+ ions in nanocrystals. Besides obtaining the elementary-state 4f and 5d electronic structure, based on the transition-state calculations we also obtained the five 4f-5d transition energies for each of these clusters.

DFT calculations of crystal-field parameters for the lanthanide ions in the LaCl3 crystal.

We present herein a calculation of crystal-field (CF) parameters for the lanthanide ions in the LaCl(3) crystal, using the density functional theory-based orbital-free embedding formalism in conjunction with the effective Hamiltonian method. The calculated values for the second- and fourth-rank CF parameters agree fairly well with the experimental data. It is found that the effect of ligand polarization plays a crucial role in determining the sign and magnitude of the second-rank CF parameters, while the effect of Pauli repulsion between 4f electrons and the ligands is important for the fourth-rank CF parameters.

Extraction of crystal-field parameters for lanthanide ions from quantum-chemical calculations.

A simple method for constructing effective Hamiltonians for the 4f(N) and 4f(N - 1)5d energy levels of lanthanide ions in crystals from quantum-chemical calculations is presented. The method is demonstrated by deriving crystal-field and spin-orbit parameters for Ce(3 + ) ions doped in LiYF(4), Cs(2)NaYCl(6), CaF(2), KY(3)F(10) and YAG host crystals from quantum-chemical calculations based on the DV-Xα method. Good agreement between calculated and fitted values of the crystal-field parameters is obtained.