Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, China.
Opt Lett. 2012 Feb 15;37(4):464-6. doi: 10.1364/OL.37.000464.
We propose and demonstrate a low-threshold single-wavelength all-fiber laser generating cylindrical vector beams using a few-mode fiber Bragg grating. Both radially and azimuthally polarized beams have been generated with very good modal symmetry and polarization purity higher than 94%. The radially and azimuthally polarized modes can be switched by simply adjusting the polarization controllers built in the fiber laser cavity. This fiber laser operates at a single wavelength of 1053 nm with a 3 dB linewidth of less than 0.02 nm, signal-to-background ratio of more than 55 dB, and a threshold as low as 16 mW. A new method for the polarization purity measurement is also proposed.
我们提出并演示了一种利用少模光纤布拉格光栅产生低阈值单波长全光纤圆柱矢量光束的方法。利用该方法产生的径向和角向偏振光束具有非常好的模式对称性和高于 94%的偏振纯度。通过简单地调整光纤激光腔内置的偏振控制器，就可以切换径向和角向偏振模式。该光纤激光器在 1053nm 的单一波长下工作，3dB 线宽小于 0.02nm，信号-背景比大于 55dB，阈值低至 16mW。同时，我们还提出了一种新的偏振纯度测量方法。
