Narrow Results

Using density functional theory combined LSDA+U method, the structural, electronic and magnetic behaviors of ytterbium implanted in wurtzite AlN were investigated. Low formation energy shows that Yb atom favors to substitute for Al site and to confirm this stability, the adsorption energy has been calculated. It is found that Al${}_{0.9375}$Yb${}_{0.0625}$N possesses a semiconductor behavior. The magnetic moment 0.9891 ${\mu }_B$ per molecule principally comes from Yb ion with small contribution from the Al and N atoms. We predict that Yb ions order ferromagnetically in AlN. The hybridization between the f orbital of the Yb atom and the p orbital of the N atom is also observed. We see that AlN:Yb will be among the good candidates for spintronic applications.

This paper presents experimental data obtained by its author on superconductive ceramics of type 1-2-3, with ytterbium as the element of rare earth. Thermal, electric and magnetic analyses are presented.

The aim of the paper is to put in evidence the effect of the substitution of Yb or Cu with Ga in the compound YbBa₂Cu₃O_7-δ, in order to compare these properties of this compound with other compounds from the same class having Y or Eu as rare earth ions.

The mono- and heteronuclear complexes of the general formula M-ATPP-Ln-L (Ln = Yb, Lu; M = Zn, Cu, 2H; ATPP - mono-p-aminotetraphenylporphyrin; L = EDTA - ethylenediaminetetraacetic acid or DTPA - diethylenetriaminepentaacetic acid) were prepared and characterized by elemental analysis, MS, ¹H NMR, UV-vis and luminescent spectra. In all compounds the lanthanide ion is coordinated by aminopolycarboxylic fragment only. The spectra of metal complexes were compared with those of free-base porphyrins. Luminescence studies showed that porphyrin fragment of ligands absorbed the visible light and transferred the energy to lanthanide (ytterbium) ion emitting in the near IR-region. Efficiency of the 4f-luminescence has been determined for d-f-metal containing porphyrin complexes in comparison with the mononuclear Yb-containing complexes in DMF solutions.

We have performed high-resolution spectroscopy of quantum degenerate gases of bosonic and fermionic ytterbium atoms using ultra-narrow intercombination transitions to probe quantum properties of the gases. The mean field interaction of the Bose-Einstein condensation and the energy distribution characteristic of the Fermi degeneracy were observed in the spectra.

Quantum degenerate ytterbium(Yb) gases in 3D optical lattices are studied for bosonic isotopes and mixtures of bosonic and fermionic isotopes. In 3D optical lattices, a quantum phase transition from a superfluid to a Mott insulating state is observed. In the deep Mott insulating regime, one-color photoassociation(PA) spectroscopy is performed to probe site occupancy. Bose-Fermi mixtures of Yb isotopes in 3D optical lattices are also studied using two different combinations of mixtures.