光折变GaAs在直流电场下双光束耦合的增强效应(英文)

Two-beam coupling and energy transfer occur, because of the birefrin-gent nature of the photorefractive grating formed by the two interfering beams. We report the observation of the enhanced two-beam coupling in the semi-insulation Cr-doped GaAs crystals at 1.15μm polarized beam from a CW He-Ne infrared laser under DC electric fields.We have measured the gain coefficients as a function of the applied DC electric field and the grating spacing. The optimum experimental crystallographic orientation in cubic photo-optic crystals with on applied field has been discussed. These measured results are close to the predicted theoretical values.     

红外光折变GaAs中的双光束耦合

报道用1.15μm红外He-Ne激光器在光折变晶体GaAs:Cr中进行相对传播双光束耦合的实验研究,给出了衍射效率和增益系数随二束光的总光强和二束光的光强比变化的实验结果。     

光折变立方晶体中的双光束正交耦合

本文报导光折变立方晶体中的双光束耦合的理论分析和实验研究,讨论了具有闪锌矿结构和具有非中心对称的43m立方晶体中的双光耦合,立方晶体具有(ε_w)_(ij)=n~2δ_j和非零电光系数的张量元γ_(ijk)=γ_(kij)=γ_(41)因此,由相干光场激发的载流子通过漂移和扩散产生空间电荷和电场,又通过线性电光效应(普克尔效应)形成折射率或电介常数空间变化的相位光枷