【英文摘要】 The reversible isomerization of trans-cis-trans under the linear polarization light, the molecules of Azo Materials have the same tropism which is vertical to the polarization of light. This presents Azo Materials anisotropy in macro scope, which means that it has photo-induced birefringence. The value of birefringence relates to optical power and the polarization angle of the light. It means we can change the birefringence of Azo Materials through modifying the status of light. Based on the characteristic, we design a new type of OPS-VECSEL which controls the polarization and frequency of the ejection laser by using Azo Materials as the optical control layer. The structure model is DBR/ Azo Materials layer /active layer/DBR. (Fig. 1)Design of DBR layerOrdinary OPS-VECSEL has a structure of single DBR, which means that one end use ejection mirror with reflection ability, the other end use the DBR. We use asymmetry double DBR in our Azo OPS-VECSEL. The growing sequence is H?L?H, and central wavelength is 600nm.Design of Optical control layerDifferent needs make us select different Azo material. There is absorption between 200-520nm and strong absorption at 488nm. We just consider the strong absorption at 488nm for simplification. Therefore we use light at the wavelength of 488nm as control light. The birefringence value of optical control layer will change when changing the intensity and polarization. Design of the active layerAccording to research of Wang lijun group in CIOMP, PVK: ALq: DCM1mixture as the active medium, Ar laser at the wavelength of 514.5nm as the pump laser, with 45°incidence angle.Analysis of controlling polarization and frequency of Azo Materials OPS-VECSELWe introduce the Azo materials into the resonator of OPS-VECSEL torealize optical control function. Through the reversible isomerization of trans-cis-trans under the linear polarization light, the molecules of Azo materials have the same tropism which is vertical to the polarization of light. This presents anisotropy of Azo materials in macroscope, which means that it has photo-induced birefringence. Based on the photo-induced birefringence effect of Azo materials, we could control the polarization and frequency of the ejection laser by using Azo materials as the optical control layer.Perfect VECSEL can be treated as isotropy medium; the fundamental mode in resonant cavity is two orthogonal modes. We call them P-polarization component and S-polarization component. The electromagnetic waves are shown like We should consider establishing the characteristic matrix of optical control layer. Through the reversible isomerization of trans-cis-trans under the linear polarization light, the molecules of Azo materials have the same tropism which is vertical to the polarization of light. This presents Azo materials anisotropy in macroscope, which means that it has birefringence. There are an effective index n? which is parallel to the polarization of pumping light andan effective index n? which is vertical to the polarization of pumping light andthe vector. Under this situation, they are no longer equal. The difference between them is the birefringence value.△n = |n(?)-n(?)|,
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