采用同步幅射白光形貌及光学显微形貌等手段研究了Ce:YAP晶体中存在的孪晶缺陷. 对孪晶的性质进行了表征, 结果表明, 它们为{101}和{121}孪晶. 经分析, 我们认为相邻且相近的晶格参数互换是孪晶形成的内在因素, 并据此建立了孪晶结构模型; 另外, 晶体生长过程中放肩阶段生长速率的突变则是导致孪晶形成的主要的外部因素.
The twin defects in Ce:YAP were investigated by using synchrotron radiation topography and etch figures. The results show that the twins are {101} and {121} types, and the exchange of neighboring lattice parameters is considered to be the intrinsic factor for twining. Based on such analysis, the twin structure model was established. Otherwise, the growth experiment results show that the abrupt change of growth rate during shoulder formation tends to cause twining.
[1] Neuroth G, Walrafen F. J. Crystal Growth, 1999, 198/199: 435--439.
[2] Wojtowicz A J, Glodo J, Lempicki A, et al. J. Phys.:Condens. Matter., 1998, 10: 8401--8415.
[3] Kapusta M, Balcerzyk M, Moszynski M, et al. Nucl. Instr. And Meth. A, 1999, 421: 610--613.
[4] Suzuki M, Toyokawa H, Mizumaki H, et al. Nucl. Instr. Meth. Phys. Res. A, 2001, 467-468: 1121--1124.
[5] Li Hongjun, et al. Journal of Inorganic Materials, 2004, 19 (5): 1186--1190.
[6] Geller S, Wood E A. Acta. Cryst., 1956, 9: 563--568.
[7] Cockayne B, Lent B, Abell J S, et al. J. Mater. Science, 1973, 8: 871--875.
[8] Savytskii D I, Vasylechko L O, Matkovskii A O, et al. J. Crystal Growth, 2000, 209: 874--882.
[9] Li H, Zhao G, Zeng X, et al. Materials Letters, 2004, 58 (26): 3253--3256.
[10] Huang X R, Hu Z W, Jiang S S. J. Appl. Phys., 1994, 75 (12): 7756--7760.
[11] 弗里埃德尔J, 王煜(译). 位错, 增订版. 北京: 科学出版社, 1984. 124.
