掺Mn钾钠铌酸锶钡晶体光折变研究

Photorefractive Properties of Mn Doped Potassium Sodium Strontium Barium Niobate Crystals

实验中，生长、极化、制备出了掺０．０２％和０．０４％Ｍｎ钾钠铌酸锶钡晶体样品，并对其二波耦合、二波耦合响应时间及自泵浦相位共轭进行了测量．研究发现：掺Ｍｎ可以有效地增加钾钠铌酸锶钡晶体的吸收，在波长６３２．８ｎｍ，０．０２％Ｍｎ晶体样品的二波耦合增益系数大于７ｃｍ－１而０．０４％Ｍｎ晶体样品的二波耦合增益系数大于９ｃｍ－１，０．０４％Ｍｎ晶体样品二波耦合增益时间响应比０．０２％Ｍｎ晶体样品二波耦合增益时间响应快近４倍；０．０４％Ｍｎ晶体样品有很高自泵浦相位共轭反射率，高达７０％．

The Mn doped potassium sodium strontium barium niobate crystals are grown, poled and polished and their two wave coupling, two wave coupling time response and self pumped phase conjugation at 632 8 nm are studied in the experiment. The two wave coupling gain are larger than 7 cm -1 and 9 cm -1 for 0 02% and 0 04% samples respectively and the two wave coupling time response of 0 04% sample is four times faster than that of 0 02% sample. Self-pumped phase conjugate reflectivity of 0 04% sample is as high as 70%. It is shown that Mn doipants can effectively increase absorption coefficient and enhance photorefractive properties of potassium soduim strontium barium niobate crystals at red wavelength.