On the Crystallization of Terbium Aluminium Garnet

Abstract

Attempts to grow terbium aluminium garnet (Tb 3 Al 5 O 12 , TAG) by the Czochralski method lead to crystals of millimeter scale. Larger crystals could not be obtained. DTA measurements within the binary system showed that TAG melts incongruently at 1840 • C. The perovskite (TbAlO 3 , TAP) with a congruent melting point of 1930 • C is the most stable phase in this system. The region for primary crystallization of TAP covers the chemical composition of TAG and suppresses the primary crystallization of the terbium aluminium garnet. Versuche zur Züchtung von Terbium-Aluminium-Granat (Tb 3 Al 5 O 12 , TAG) nach der Czochralski -Methode erbrachten Kristalle mit Größen im Millimeter-Bereich. Die Züchtung größerer Kristalle mißlang. DTA -Messungen im binären System ergaben, daß TAG inkongruent bei 1840 • C schmilzt. Der Perovskit (TbAlO 3 , TAP) ist mit einem kongruenten Schmelzpunkt von 1930 • C die stabilste Phase in diesem System. Das Primärausscheidungsgebiet von TAP schließt die chemische Zusammensetzung des TAG mit ein und unterdrückt die Erstkristallisation des Terbium-Aluminium-Granats.

Synthesis and photoluminescent properties of Ce3+ doped terbium aluminum garnet phosphors

“…Fig. 1 shows the X-ray powder diffraction (XRD) results of the precursor and products as calcined at different temperatures for 2 h. The precursor is amorphous as calcined at temperatures below 850 • C. The precursor is almost converted to TAG however with a little TbAlO 3 (terbium aluminum perovskite, TAP) peaks as calcined at 900 • C. In the binary system of Al 2 O 3 -Tb 2 O 3 , the perovskite structure of TAP always goes behind the TAG evolution [12]. Pure TAG phase powder is obtained as calcined at temperatures above 1000 • C. Fig.…”

Faraday Isolators for High Average Power Lasers

“…Two other terbium garnets have V 35% higher than TGG: TAG (Ganschow et al, 1999;Rubinstein et al, 1964;Geho et al, 2005) and TSAG (Yoshikawa et al, 2002). Verdet constants of LiTb(MoO 4 ) 2 (Guo et al, 2009) and NaTb(WO 4 ) 2 (Liu et al, 2008) are even higher.…”

Growth mechanism of incongruently melting terbium aluminum garnet (Tb3Al5O12; TAG) single crystals by laser FZ method

“…A semi-qualitative evaluation of the WDS map showed the x value of the melt to be around 0.22. The proposed phase diagram of the Tb 2 O 3 -Al 2 O 3 system [3] is shown in Fig. 5 with the horizontal axis of x.…”