BeAl_6O_(10)晶体中的Cr^(3+)发光中心  

Chromium center in BeAl_6O_(10):Cr crystal

作　　者：吴光照[1] 马笑山[1] 沈雅芳[1] 张秀荣[1] 徐军[1] 张新民[1] 

机构地区：[1]中国科学院上海光学精密机械研究所

出　　处：《光学学报》1990年第11期975-979,共5页Acta Optica Sinica

摘　　要：铬激活的BeA1_6O_(10)(BHA)晶体中Cr^(3+)离子形成多种发光中心,给出复杂的发光.发光谱中包含着荧光寿命为几十微秒至几毫秒不同的光谱成分,本文用Chrono光谱法分离子这些重迭的成分,辩认出三种铬中心——两种强场中心,Cr(Ⅰ)和Cr(Ⅱ),一种低场中心,Cr(Ⅲ).并且给出了它们占据的格位.一个单胞里可能的铬格位共有40个.其中,24个畸变了的八面体格位属于Cr(I)型中心;8个畸变较小近乎正八面体的格位属于Cr(Ⅱ)型中心;另外8个格位具有次近邻微扰结构,属于Cr(Ⅲ)型中心.Cr(Ⅲ)给出宽带发射.Cr3+ ions in the BeAI6O10 (BHA) crystal give complicated luminescenoe spectrum with different fluorescence lifetimes from several miliseconds to several ten miorosceco-nds. 'Null point phases' of these components measured by using chrono-speotroscopio technique indicate that the spectrum is due to two high-field single Cr3+-centers, Cr (Ⅰ), Cr (Ⅱ), and a low-field single Cr3+-center, Cr (Ⅲ). The crystal structure shows that, in an unit cell the possible chromium sites are 24 Cr (Ⅰ) with six distortion maners and 8 Cr (Ⅱ), responsible for the main line emission, and 8 Cr (Ⅲ) with a particular structure responsible for the broad band emission. At 77K, some lenes have been identified as the transitions of Cr (Ⅰ), Cr (Ⅱ) and the Cr-pairs of the Ⅰ-Ⅰ and Ⅰ-Ⅱ types.

关 键 词：BeAl6O10 晶体 发光中心 光谱 

分 类 号：O734.3[理学—晶体学]