光纤回音壁模式的三波段激光辐射研究  

Three-wavelength-range Whispering-gallery-mode Fiber Lasing Emission

作　　者：祝昆[1] 江楠[1] 韩德昱[1] 张远宪[1] 普小云[1] 

机构地区：[1]云南大学物理系,昆明650091

出　　处：《光子学报》2009年第12期3061-3066,共6页Acta Photonica Sinica

基　　金：国家自然科学基金(60877037;10564005)资助

摘　　要：将石英光纤浸入低折射率的激光染料溶液中构成圆柱形微腔.采用沿光纤轴向光抽运的消逝波激励增益方式,获得了沿光纤轴向长距离的激光染料增益,受激辐射光在圆柱形微腔中回音壁模式的支持下形成激光振荡.在直径为288μm的同一根光纤外分三段分别填入罗丹明6G、罗丹明610和罗丹明640激光染料乙二醇溶液,实现了波长分别在567～575nm、605～614nm和656～666nm三个不同波段的回音壁模式激光振荡,用一根光纤同时获得了红、橙、黄三种不同颜色的激光辐射.对实验所获得的回音壁模式激光光谱做了模式标定,依据标定的模式数计算了各种模式以及抽运光在光纤截面的强度分布.计算结果表明,激光增益区域总是局限在圆柱形微腔回音壁模式的模场区域内,由此可以显著地提高抽运效率,增加抽运光沿光纤轴向的增益长度.A cylindrical micro-cavity was made by immersing a silica optical fiber into a low refractive index dye solution. Optically pumped by evanescent wave along the fiber axis, a long dye gain distance along the fibre axis was obtained, and lasing emission supported by Whispering-Gallery-mode in cylindrical micro-cavity was observed. When a fibre diameter 288 μm was immersed into three glass capillaries filled separately with Rhodamine 6G、Rhodamine 610 and Rhodamine 640 dye ethylene glycol solution, Whispering Gallery Mode laser oscillation in the wavelength ranges of 567-575 nm、605-614 nm and 656-666 nm were observed, three-color lasing emission （red, orange and yellow） from a single optical fibre was realized. The obtained lasing spectra were mode assigned, the spatial intensity distributions of the assigned modes and pumping energy along the fiber’s cross section were calculated. The computational results show that dye gain is confined in the evanescent field of Whispering Gallery Mode of the fiber, which leads to a high pumping efficiency and a long gain distance along the fiber axis.

关 键 词：光纤激光器 回音壁模式 消逝波激励 三波段激光辐射 

分 类 号：TN248[电子电信—物理电子学]