Li_2O-BaO-TiO_2-TeO_2透明微晶玻璃的二阶非线性光学效应

Second harmonic generation effect of transparent Li_2O-BaO-TiO_2-TeO_2 crystallized glasses

采用热处理方法制备Li2O-BaO-TiO2-TeO2微晶玻璃,X射线衍射和透射光谱证实获得了含Li2TeO3微晶的透明微晶玻璃.采用Maker条纹法研究了微晶玻璃的二阶非线性光学效应,结果表明:玻璃中的Li2TeO3微晶诱导了二阶非线性光学效应的产生,且当基频光入射角为±60°左右时,二次谐波强度出现最大值;随热处理温度的升高和时间的延长,玻璃的二次谐波信号先逐渐增强后明显下降,这是玻璃中的微晶先逐渐长大,结晶程度变好,并择优取向生长,随后微晶明显长大,玻璃的透过率降低,散射明显增强所致.

Crystallized glasses of Li2O-BaO-TiO2-TeO2 system were prepared by heat treatment method. The results of XRD （X-ray diffractomer） and transmittance spectrum show that transparent crystallized glass containing Li2TeO3 are obtained. The second harmonic generation （SHG） effect of the crystallized glasses was studied by utilizing Maker fringe technique. The results indicate that Li2 TeO3 in the glass induced the SHG effect, which reached the maximum when the incidence angle was near ± 60°. The SHG intensity gradually increased and then apparently decreased with the increase of temperature and period heat treated. The reasonable explanation for this can be given ; the gradual growing up of the Li2TeO3 microcrystal led to the increase of crystalline degree and formation of Li2TeO3 microcrystal in a preferred orientation in the glass, in addition, the continuously growing-up of Li2TeO3 microcrystal can also result in the enhancement of scattering and decrease of transmittance.