摘要
在室温下测量了Li_2B_4O_7单晶的各种振动类的偏振Raman散射谱和该晶体粉末样品的红外吸收谱(200—4000cm^(-1))。根据LO-TO劈裂的实验结果,计算出该晶体极化模的有效电荷和振子强度。通过与BBO和LBO晶体的结构和B—O伸缩振动模频率比较,得出:Li_2B_4O_7晶体可能有较大的非线性光学系数。
Polarized Raman spectra of single crystal Li2B4O7 have been measured in the wavenum-ber shift range of 50-3000cm-1 at room temperature. The infrared absorption spectrum of Li2R4O7 has also been measured in the range of 200-4000cm-1 for powder samples dispersed in the pressed KBr disks. Based upon the experimental results of LO-TO splitting, the effective charge and mode strength of polar modes are calculated. A comparison of the structure and B-O stretching vibration frequency of various borate species suggests comparatively high nonlinear optical efficiency of Li2B4O7 crystals.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
1993年第1期154-160,共7页
Acta Physica Sinica
