Albedo and gain threshold of a diffusive Raman random laser

OPTICS COMMUNICATIONS

卷:284

Article

Selden, A. C.¹ 

[1] Univ Zimbabwe, Dept Phys, Harare, Zimbabwe

关键词: Random laser;    Raman scattering;    Diffusion;    Albedo;   

DOI  :  10.1016/j.optcom.2011.06.021

来源: Elsevier

【 摘 要 】

The diffuse reflectance (albedo) and transmittance of a Raman random gain medium are derived from a diffusion equation with power dependent gain. The results show good agreement with the experimental data for barium nitrate powder. Both the Raman albedo A(R) and Raman transmittance T-R diverge at a critical gain gamma(c), interpreted as the threshold for diffusive Raman laser generation. The parametric dependence of the albedo and threshold gain on the scattering characteristics of the random medium is analysed and the feedback effect of Fresnel reflection at the gain boundaries evaluated. The addition of external mirrors, particularly at the pumped surface, significantly reduces the generation threshold. (C) 2011 Elsevier B.V. All rights reserved.

【 授权许可】

Free