研究了外加电场对高斯光束在光伏光折变晶体中传播特性的影响。结果表明，对于给定的高斯光束和光伏光折变晶体，在某些外加电场下，该光束能演化成稳定的屏蔽光伏空间明孤子。在另一些外加电场下，高斯光束在传播过程中则呈现出周期性的压缩和膨胀现象。外加电场的强度和极性对稳态屏蔽光伏明孤子的空间波形有显著的影响。相比之下，极性的影响更大。

The impact of an applied field on the propagation of a Gauss beam in the photovotaic-photorefractive crystal is investigated. It indicates that, in a photovotaic-photorefractive crystal with a proper applied field, a Gauss beam can evolve into steady-state bright screening-photovoltaic optical soliton. If the applied field is not proper, the Gauss beam will experience cycles of compression and expansion. The intensity and polarity of the applied field have a remarkable influence on the wave shape of steady state bright screening-photovoltaic optical soliton. However, the polarity has a larger influence on it as compared with the intensity of the applied field.