Electro-optic and electro-gyration effects on light propagation in \bf \overline 4 2mpoint-group crystals

Abstract

Several nonlinear crystals that are used in laser and optical signal processing technologies belong to the 42m point group. This group exhibits as primary effects natural birefringence, optical activity, linear and quadratic electro-optic effects, and linear and quadratic electro-gyration effects, and, as secondary effects, photo-elasticity and piezo-gyration via the inverse piezo-electric phenomenon. The combination of these effects makes the study of light propagation a complicated task. In this work, the influence of each of these effects on light propagation is analytically reviewed, and suitable configurations for the light propagation and applied electric field directions are identified, which decouple the contribution of the individual effects. It is found that the complete decoupling of the linear electro-gyration from the linear electro-optic effect is not possible for this symmetry, while the inverse is feasible, and that the separation of the quadratic from the linear electro-optic effect can be achieved. For the linear phenomena, index ellipsoid geometries and eingenpolarizations are calculated, and analytic expressions are derived for the intensity of a light beam propagating through a crystal followed by a polarizer, thus providing valuable information for the design of devices and/or measurements of corresponding coefficients. ‡ Present address: Helmholtz Zentrum Mü nchen,

Effect of optical activity on electro-optic measurements in crystals of the potassium dihydrogen phosphate family

“…According to the form of the linear electro-optic tensor in 42m symmetry crystals (see Table 2) the linear electro-optic coefficient r 63 will affect only the component B 12 of the impermeability tensor when E Z 6 ¼ 0. There are two optimal measurement configurations, which have already been identified previously (see, e.g., Efremidis et al, 2011). When the phenomena nonlinear in E are omitted, the components of the impermeability tensor are real:…”

“…In equation 6, combinations of the electro-optic effects with the optical activity give negligible results; thus the approximation Re [B] ' Re[B (0) ] is applied here, as previously by Efremidis et al (2011). Consequently, the complex Hermitian impermeability tensor is given by…”

“…In recent years the accuracy of measurements of electro-optic coefficients has become so high that the contributions of these weaker electrogyration effects have to be considered. To the best of our knowledge, such analysis has been initiated only by Efremidis et al (2011). This interesting work is focused on the linear effects, for which some analytical relationships are presented without final results of calculations, while the analysis of the quadratic effect was limited to the components of the impermeability tensor.…”

“…An analytical derivation of the response of the light modulator is a rather complicated task when the combination of the linear birefringence, natural optical activity, and electrooptic and electrogyration effects is considered. The final formulas describing the emerging light intensity, reported previously in the literature, have the form of nonlinear equations with several additional variables related to the birefringence and polarization state of the light waves propagating in the crystal (Efremidis et al, 2011). The electric field applied to the crystal may affect each of the variables, and in general cases all the changes may have a significant impact on the intensity of the emerging light.…”

Электросенсор На Основе Эффекта Электрогирации В Кристалле Вольфрамата Свинца

“…DOI: 10.21883/PJTF.2017.08. 44530.16496 Явление оптической электрохиральности было открыто более 50 лет назад и до настоящего времени привлекает исследователей [1,2]. Первое предложение использовать эффект электрохиральности для измерения высоковольтных электрических напряжений было сделано в работе [3] на примере кристаллического кварца.…”