Growth of Yttrium Vanadate Crystal by Modified Floating Zone Technique

Abstract

A surface acoustic wave (SAW) substrate for a duplexer, such as a Personal Communication Service handy phone system in the U.S.A, is required to have a good temperature stability, an optimum electromechanical coupling factor, and a large reflection coefficient. The conventional method of depositing a SiO 2 film on a thick Al electrode/LiTaO 3 substrate to improve its temperature coefficient of frequency (TCF) is not effective for SAW resonator-type devices, because good frequency characteristics are not obtained due to large convex portions on the surface of SiO 2 film. However, resonators having a large reflection coefficient, an excellent TCF, and good frequency characteristics were realized using the following two new structures: (I) SiO 2 film/grooved Al electrode/LiTaO 3 structure and (II) reflection of a shear horizontal (SH) wave at free edges on a SiO 2 film/thin Al electrode/LiTaO 3 structure substrate.

Growth of high quality and large-sized Nd3+:YVO4 single crystal

“…The relationship between the growing habit and characteristics and the structural characterization of YVO 4 crystal were discussed. The lasing property of 0.5 at% Nd-doped YVO 4 light conversion efficiency is 54.8%, and the slope efficiency is 59%. As compared with the literature, the grown Nd 3+ :YVO 4 crystal has a large size, optical homogeneity, high light-light conversion efficiency and slope efficiency.…”

“…As is well known, the Nd 3+ -doped YVO 4 crystal is a current excellent laser crystal with diode-pumped, since it has a low pumping threshold, large emission section, large absorption coefficient and so on. However, Nd 3+ :YVO 4 crystals with high-quality and large-size crystals were difficult to grow.…”

“…However, Nd 3+ :YVO 4 crystals with high-quality and large-size crystals were difficult to grow. Previously many reported the growth of pure YVO 4 and rare earth-doped YVO 4 crystals by means of different growth techniques (including Czochralski, Verneuil, floating zone, Bridgman, LHPG and TSSG method) . Recently, the present authors and others reported the crystal growth of Tm 3+ /Yb 3+ -codoped YVO 4 with high quality and dimension +25 Â 35 mm 2 [18], Nd 3+ -doped YVO 4 crystal with dimension +30 Â 40 mm 2 [19] and pure YVO 4 crystal with high quality and dimension +42 Â 42 mm 2 [21], respectively.…”

Crystal growth of rare-earth orthovanadate (RVO4) by the floating-zone method

“…Slow cooling from solution [1], the Czochralski process [2], top-seeded solution growth [3], the laser-heated pedestal growth method [4], the floating-zone (FZ) method [5] and the micro-FZ method [6] have been reported. All crystals obtained by these methods were of excellent quality, although their size was small.…”

Ab initio LSDA+U Study of Optical Properties of RVO4 (R = Eu, Ho, Lu) Compounds

“…On another hand and due to the importance of RVO 4 crystals growth with good and large dimensions, several methods have been reported, like the Czochralski process, slow cooling from solution, topseeded solution growth, laser-heated pedestal growth method, floating-zone (FZ) method and micro-FZ method. [21][22][23][24][25][26] For example, the importance of YVO 4 (Y: Yttrium) originates from the fact that though Nd lasers was marginal for decades because of serious problems encountered during the growth of YVO 4 crystals by the costly Czochralski method, 27 but the increasing demand for compact, low cost devices has raised the interest for single crystal fibers whose advantage is that they can be successfully used for the construction of high efficiency miniature lasers with single mode 4 and LuVO 4 reported yet. Describing the medium response to an applied electromagnetic radiation within the framework of linear response theory, the optical properties of a material change or affect the characteristics of light passing through it by modifying its propagation vector or intensity.…”