Electron paramagnetic resonance (EPR) is used to identify the different substitution sites of Yb3+ ions in the LuVO4 host. Three different types of sites are observed. One site, referred to as YbI, with tetragonal D2d symmetry characterized by g-values of and , corresponds to 80% (50%) of the total number of Yb3+ ions for the 1% (5%) doped compound. Two other tetragonal sites, referred to as YbII a,II b, with the same D2d symmetry and characterized by g-values of , and , , represent 20% (50%) of the total number of ytterbium ions for the 1% (5%) compound. One minor site, referred to as YbIII, corresponding to less than 1% of the Yb3+ ions, with a lower C2v or D2 symmetry, is also seen in the EPR spectra. The temperature dependence of the EPR linewidth is studied and shows for all the sites a dominant Orbach process for the spin-lattice relaxation time T1 for T>12 K.
Electron paramagnetic resonance study of the multisite character of Yb3+ ions in LuVO4 single crystals
BETTINELLI, Marco Giovanni;
2005-01-01
Abstract
Electron paramagnetic resonance (EPR) is used to identify the different substitution sites of Yb3+ ions in the LuVO4 host. Three different types of sites are observed. One site, referred to as YbI, with tetragonal D2d symmetry characterized by g-values of and , corresponds to 80% (50%) of the total number of Yb3+ ions for the 1% (5%) doped compound. Two other tetragonal sites, referred to as YbII a,II b, with the same D2d symmetry and characterized by g-values of , and , , represent 20% (50%) of the total number of ytterbium ions for the 1% (5%) compound. One minor site, referred to as YbIII, corresponding to less than 1% of the Yb3+ ions, with a lower C2v or D2 symmetry, is also seen in the EPR spectra. The temperature dependence of the EPR linewidth is studied and shows for all the sites a dominant Orbach process for the spin-lattice relaxation time T1 for T>12 K.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
