Abstract In this paper, the enhancement of light-induced scattering in congruent SBN:Cr (Sr$_{0.61}$Ba$_{0.39}$Nb$_2$O$_6$:Cr) crystals in the presence of an externally applied electric field and its suppression are studied. If a coherent image is focalized in SBN:Cr crystal without applying external electric field, the output image will remain clear, because of the weak photorefractive effect in the crystal. When a field is applied properly along the crystal axis, markedly enhanced scattering from the signal beam and the output image dispersion can be observed due to the increase of the photorefractive two-beam coupling gain and the light-induced index change in SBN:Cr crystals. By introducing a coherent or incoherent beam with higher intensity the light-induced scattering can be suppressed through the erasure of scattering gratings. The difference between coherent and incoherent beam is that the former can also amplify the signal beam as the scattered light is removed, whereas the latter can only make the signal beam revert to its initial state. The results obtained under different experimental conditions are consistent with theoretical analysis.
Received: 28 August 2003
Revised: 27 November 2003
Accepted manuscript online:
(Other nonlinear optical materials; photorefractive and semiconductor materials)
Fund: Project supported by the National Natural Science Foundation of China (Grant No 60077018).
Cite this article:
Zhao Jian-Lin (赵建林), Li Zhen-Wei (李振伟), Yang De-Xing (杨德兴), Ma Yang-Hua (马仰华) Light-induced scattering in SBN:Cr crystal under external electric fields and its suppression 2004 Chinese Physics 13 1464
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.