Study on defects in hydrothermal-grown KBe2BO3F2 crystals

✍ Scribed by Jinqiu Yu; Lijuan Liu; Xiaoyang Wang; Haitao Zhou; Xiaoling He; Changlong Zhang; Weining Zhou; Chuangtian Chen

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 833 KB
• Volume: 318
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2010.09.082

✦ Synopsis

Sizeable crystals of KBe 2 BO 3 F 2 (KBBF) were successfully grown by the hydrothermal method, but their conversion efficiency of second harmonic generation (SHG) was much lower than that of the flux grown crystals. In order to find the reason, extensive studies on defects in hydrothermal-grown KBBF crystals were carried out for the first time. Dislocations, grain boundaries and twins were revealed and observed on the (0 0 1) plane of hydrothermal-grown KBBF crystals by chemical etching and microscopy. X-ray rocking curves indicate the hydrothermal-grown crystals are of poor crystalline quality. Moreover, powder X-ray diffraction measurements show some small unidentified peaks for hydrothermal-grown KBBF crystals. Powder SHG intensities of hydrothermal-grown KBBF crystals were found to be several times lower than those of the flux grown ones. These indicate the hydrothermal-grown KBBF crystals may contain structural defects.