Growth, spectroscopy, and stimulated emission of cubic Bi4Ge3O12 crystals doped with Dy3+, Ho3+, Er3+, Tm3+, or Yb3+ ions

Abstract

Growth, spectral and laser properties of Bi,Ge,O,, crystals doped with TR3+ (Dy3+, Ho3+, Tm3+, Er3+, or Yb3+) ions, are investigated. Absorption and luminescence spectra of Er3+ and Yb3+ ions are analysed and their crystal-field splitting schemes according t o energies u p t o 18400 cm-l determined. Using the Judd-Ofelt approach of electric-dipole transitions, the integral absorption coefficients of Er3+ ions are analysed. The intensity parameter Qt, transition probabilities from some excited states, and inter-manifold luminescence branching ratios are calculated. Ergebnisse uber Ziichtung, Spektroskopie und Lasereigenschaften von Bi,Ge,O,,-Einkrist~Ilen, dotiert mit den Seltenerdionen Dy3+, Ho3+, Tm3+, Er3+ bzw. Yb3+, werden mitgeteilt, weiterhin fur Er3+ und Yb3 + die Absorptions-und Lumineszenzspektren sowie die Aufspaltungsschemata im Kristallfeld. Die integralen Absorptionskoeffizienten von Er3+-Ionen werden anhand der Judd-Ofelt-Naherung fur elektrische Dipoliibergange snalysiert und der Intensitatsparameter Q t , die Ubergangswahrscheinlichkeiten einiger angeregter Zustande und die Verzweigungsverhaltnisse in die verschiedenen Lumineszenzkanale berechnet . 2. Crystal Growth and Investigation Methods 2.1 Growth of Bi,Ge,O,,:TR3+ single crystals Single crystals of bismuth germanate were grown from the melt (melting point 1044 "C) by the Czochralski technique [cf. 1, 3 to 6, 8, 91 using platinum crucibles and rf heating. Stoichiometric amounts of Bi,O,, TR,O,, and GeO, (each of 99.99% purity) 47*

Nd: Bi4Ge3O12 crystal growth by czochralski method

“…It is known that Nd 3 § ions substitute for Bi 3+ ions with relative ease. Kaminskii et al [8] suggested that the crystallochemical behavior of the Bi 3 § ion is more closely related to such larger rare earth trivalent ions as Nd 3 § than to the smaller rare earth trivalent ions, Dy 3 § to Yb 3 § Kaminskii et al's [8] argument agrees with our experiments in that the Nd-doped BGO crystals were . 3 § Er3 § grown more easily than crystals doped with Ho , and Tm 3 § Compared to the pure BGO crystal, Nd:BGO crystal has almost the same d values and intensities as shown in Fig.…”

“…The BGO crystal has a relatively low melting temperature (1044~ and can be easily grown. The Nd 3 § ion, that has a large ionic radius among the trivalent rare earth metals, is similar in chemical and crystallographic behavior to the Bi 3 § ion [8], so the Nd ~ § ion can be doped easily into the BGO crystal. Feng et al [7] grew an Nd:BGO crystal with the Bridgman-Stockbarger method, and compared the optical absorption spectrum of Nd:BGO with that of Nd:YAG at about 800nm, which is the wavelength of the LD pumping source.…”

Growth and spectroscopic properties of Yb:BSO single crystal

“…Trivalent rare-earth ions enter the BSO lattice substitutionally at Bi 3 + sites (C 3 symmetry). The crystallochemical behavior of Bi 3 + ions is more closely related to such larger rare earth trivalent ions [12]. Therefore, taking into account that Yb 3 + has the ionic radius $ 0.101 nm smaller to that of Bi 3 + (0.117 nm), one can suggest that Yb 3 + ions substitute for Bi 3 + ions easily due to their similar crystallochemical behavior.…”

Design of 154 kV Extra-High-Voltage Prototype SF6 Bushing for Superconducting Electric Power Applications

“…Single crystals of Bi4Ge3OI2 have attracted considerable attention owing to their applications as scintillators [l] and non-linear optical devices [23 and for their potential as solid state laser host [3]. Also, photorefractive properties have been described recently for single crystals doped with Cr ions [4].…”