Elastic, piezoelectric, dielectric properties of La/sub 3/Ga/sub 5.5/Ta/sub 0.5/O/sub 14/ single crystals

Crystal growth and dielectric, piezoelectric and elastic properties of Ca3NbGa3Si2O14 single crystal

“…They were prepared by mixing stoichiometric amounts of CaCO 3 SiO 2 powder of 4 N purity. The oxides were ground, mixed and pressed into tablets and then the tablets were put into a Pt crucible.…”

“…Recent progress in electronic technology requires new piezoelectric crystals with high electromechanical coupling factors and a high thermal stability of frequency. Single crystals of compounds with the Ca 3 Ga 2-Ge 4 O 14 (CGG) (point group 32, space group P321) structure have been reported to be promising piezoelectric materials for fabrication of filters with large pass bandwidths and oscillators with high-frequency stability [1][2][3][4]. However, most CGG-type crystals such as La 3 Ga 5 SiO 14 (LGS), La 3 Nb 0.5 Ga 5.5 O 14 (LGN) and La 3 Ta 0.5 Ga 5.5 O 14 (LGT) are disordered.…”

Growth and piezoelectric properties of R3Ga5SiO14 and RCa4O(BO3)3 (R: rare-earth elements) single crystals

“…2 shows the dependence of the piezoelectric modulus, d 11 , on the lattice parameter, a, in the RGS-type crystals. The d 11 data were collected from the literature (Pr 3 Ga 5 SiO 14 [10], La 3 Nb 0.5 Ga 5.5 O 14 [11], La 3 Ta 0.5 Ga 5.5 O 14 (LTG) [12], La 3 Al x Ga 5−x SiO 14 [13], Sr 3 Ga 2 Ge 4 O 14 [14] and Na 2 CaGe 6 O 14 [15]). As can be seen from Fig.…”

“…2 and 4, we first synthesized the Sr 3 TaGa 3 Si 2 O 14 single crystals. The electromechanical coupling factor, k ij , of this crystal was comparable to that of LTG with the highest k ij values [12]. Moreover, we synthesized new RGS-type Ba 3 TaGa 3 Si 2 O 14 (BTGS) single crystals.…”

Sol–gel preparation of a new compound with Ca3Ga2Ge4O14 structure: La3Al5.5Ta0.5O14

“…These favorable properties suggest the utilization of these compounds for acousto-electronic applications in devices based on bulk (BAW) and surface acoustic waves (SAW) operating at high temperatures or piezo mechanical pressure, power and acceleration sensors, as well as for resonator materials for miniaturized band pass filters with low insertion losses as required for satellite microwave and mobile terrestrial communications [4]. Among this group of materials, LGN and LGT have considerably larger dielectric constant e 33 and piezoelectric coefficient d 11 than LGS [5][6][7].…”