EPR and optical spectroscopy of Yb3+ ions in CaF2: an analysis of the structure of tetragonal centers

Abstract

CaF 2 crystals doped with Yb 3+ ions have been studied by electron paramagnetic resonance (EPR) and optical spectroscopy. EPR spectra of paramagnetic centers (PCs) for eubic (Te) and tetragonal (T,ot) symmetries were identified. Empirical energy level diagrams were established and crystal field parameters were determined. Information on the CaF2:Yb 3 § phonon spectra was obtained from the electron-vibrational structure of the optical spectra. The crystal field parameters were used to analyze the crystal lattice distortions in the vicinity of the Yb 3 § ion. Within the framework of a superposition model, ir is established that four F-ions located symmetrically with respect to the fourfold axis from the side of the ion-compensator approach the impu¡ ion and deviate from the PC axis. The second set of four fluofine ions also approaches the Yb 3+ ion and the PC axis. The ion-compensator F-also approaches considerably the impu¡ ion.

A unified calculation of the optical spectral band positions and electron paramagnetic resonance spectral data for Yb3+ in InP semiconductor

“…If the covalence of cluster is stronger, the spin-orbit parameter will be smaller. For Yb 3+ ion in crystals, a lot of studies of optical and EPR spectra showed that ≈ 2900 ± 50 cm −1 [9,11,[16][17][18][19][20]. For InP:Yb 3+ , the small spin-orbit parameter (≈2860 cm −1 , which is very close to the value, 2864 cm −1 , obtained by analyzing only the optical spectrum in Ref.…”

Investigations of the optical spectra and spin-Hamiltonian parameters for the rhombic Yb3+ centers in garnets

“…For Yb 3+ ion in crystals, we have zE2900750 cm À1 [12,13,[21][22][23]36]. Our parameters z used in Yb 3+ -doped garnets (listed in Section 2) are within the range and can be regarded as reasonable.…”

High Repetition Rate Yb:CaF₂ Multipass Amplifiers Operating in the 100-<roman>mJ</roman> Range

“…As every Yb-doped fluoride [41], Yb:CaF 2 exhibits a very broad and smooth emission band, which is exceptional for a well-structured cubic crystal. This is explained by the different valences between the dopant (Yb 3+ ) and the substituted alkaline cations (Ca 2+ ), which induces the creation of clusters during the doping process [42][43][44][45]. This clustering occurs already at the lowest doping levels but it really becomes preponderant for Yb-doping above 0.5-at.…”