A family of langasite: growth and structure

Single-crystal growth of langasite (La3Ga5SiO14) by the vertical Bridgman (VB) method in air and in an Ar atmosphere

“…In both temperatures, the resistivity of the crystal grown in an Ar atmosphere was about one-order higher than that grown in air. This result is extremely different from the results reported by Domoroshchina et al [5,6] that CZ-LGS grown crystal in an Ar atmosphere showed lower resistivity than that of CZ-LGS crystal grown in oxygen-containing Ar atmosphere. They supposed incorporation of high concentration of oxygen vacancies induced during the former growth process.…”

“…An arrow indicates the interface between the seed and the grown crystal. The color of the LGS crystal grown in air was a transparent orange, which was consistent with that reported previously [7] and that grown by CZ method [3][4][5][6]. Fig.…”

“…LGS crystals have generally been grown industrially by the Czochralski (CZ) method using an iridium crucible [3][4][5][6]. During CZ growth, an Ar atmosphere containing several percent of oxygen has normally been applied to avoid evaporation of Ga atoms from the melt and oxidation of the iridium crucible [3][4][5][6].…”

“…During CZ growth, an Ar atmosphere containing several percent of oxygen has normally been applied to avoid evaporation of Ga atoms from the melt and oxidation of the iridium crucible [3][4][5][6]. Electric properties of such grown CZ-LGS crystals were reported [5,6]. Our group succeeded in growing an LGS column crystal, 2 in.…”

Luminescence of Eu-doped langanite nanopowders synthesized by a citrate sol–gel method

“…the reddish coloration of the samples is intensified with the annealing temperature). The red coloration of the crystals from the langasite family is related to point defects involving oxygen [14][15][16].…”