Growth of a new lithium tantalate that is stoichiometric with congruent composition by employing the extended concept of stoichiometry

2014 Fiscal Year Final Research Report

• Project/Area Number: 24360002
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Applied materials science/Crystal engineering
• Research Institution: Tohoku University
• Principal Investigator: UDA Satoshi 東北大学, 金属材料研究所, 教授 (90361170)
• Co-Investigator(Kenkyū-buntansha): SHOJI Ichiro 中央大学, 理工学部, 教授 (90272385)
• Co-Investigator(Renkei-kenkyūsha): KOIZUMI Haruhiko 東北大学, 金属材料研究所, 助教 (10451626)
• Research Collaborator: MAEDA Kensaku 東北大学, 大学院工学研究科, 助教 (40634564)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: タンタル酸リチウム / 化学量論 / 調和融解組成 / 結晶化起電力 / 波長変換 / 自由度

Outline of Final Research Achievements

By employing a new concept of stoichiometry of a material where the activity of any constituent element could be unity, we developed a new lithium tantalate with MgO doping, cs－MgO:LT (Li2O: Ta2O5: MgO = 40.8:50.0:9.2), that is stoichiometric and coincident with the congruent composition. Because of this coincidence, cs-MgO:LT does not yield crystallization electromotive force and does not show segregation during growth even for ionic species. A bulk crystal was grown from the melt of the cs－MgO:LT composition via the Czochralski (CZ) method, and it showed excellent compositional homogeneity, which was proved by the constant distribution of the Curie temperature throughout the crystal.

Free Research Field

結晶成長