Electrogyration and Faraday rotation in pure and Cr-doped lead germanate crystals
Electrogyration and Faraday rotation in pure and Cr-doped lead germanate crystals
复制标题
纯锗酸铅晶体和掺铬锗酸铅晶体中的电旋和法拉第旋转
DOI：
10.1088/0953-8984/20/7/075201
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
O. Vlokh
中科院分区：
文献类型：
--
作者：
D. Adamenko;I. Klymiv;V. M. Duda;R. Vlokh;O. Vlokh
本文报道了Pb5Ge3O11和Pb5Ge3O11：CrPb5Ge3O11晶体在相变过程中电回转(EG)效应、法拉第旋转和自然旋光性随温度变化的研究结果。Pb5Ge3O11：Cr晶体具有较高的EG系数。我们证明了Pb5Ge3O11：Cr晶体的居里-魏斯常数、序参数和介电常数的临界指数以及热力学势系数是如何从光学活性和EG系数的温度依赖关系中得到的。Pb_5Ge_3O_(11)和Pb_5Ge_3O_(11：Cr)晶体在相变时的法拉第旋转角的增大是由自发极化引起的磁光复合效应引起的。它与自发极化的平方成正比。我们揭示的这一现象对应于晶体光学的综合效应，它是由于不同场的共同作用而出现的。
We present the results of studies on the temperature dependence of the electrogyration (EG) effect, Faraday rotation and natural optical activity in Pb5Ge3O11 and Pb5Ge3O11:Cr crystals at the phase transition. A high EG coefficient is found for Pb5Ge3O11:Cr crystals. We demonstrate how the Curie–Weiss constant, the critical exponents of the order parameter and the dielectric permittivity in Pb5Ge3O11:Cr crystals, as well as the coefficients of thermodynamic potential, could be derived from the temperature dependences of optical activity and the EG coefficient. We also show that the increment of the Faraday rotation in Pb5Ge3O11 and Pb5Ge3O11:Cr crystals appearing at the phase transition is caused by a combined magneto-electrooptic effect induced by spontaneous polarization. It is proportional to the square of spontaneous polarization. The phenomenon revealed by us corresponds to combined effects of crystal optics, which appear due to the common action of different fields.