Coiling technique is used to control the transverse mode of a large-mode-area （LMA） multimode fiber laser. By winding the fiber to a coil with different radius, high-order modes of a multimode fiber laser are suppre...Coiling technique is used to control the transverse mode of a large-mode-area （LMA） multimode fiber laser. By winding the fiber to a coil with different radius, high-order modes of a multimode fiber laser are suppressed one by one and finally 15.4-W single-transverse-mode output is achieved when the coil radius is 20 mm. It is found that as the coil radius decreases, the beam quality of a multimode fiber laser gets better but the slope efficiency drops for higher-order modes are discriminated. During the experiment, as the coil radius of multimode fiber changes, output characteristic of the laser has been measured. Meanwhile, the mode loss of different modes is calculated theoretically. It is proved that the experimental measured results fit well with the theoretically calculated results.展开更多
Coiling technique is used to suppress high-order modes of a large mode area （LMA） double clapt multimode fiber. Output powers and beam quality factors M^2 are measured under two different coiling radii. 217 W with M...Coiling technique is used to suppress high-order modes of a large mode area （LMA） double clapt multimode fiber. Output powers and beam quality factors M^2 are measured under two different coiling radii. 217 W with M^2 of 2.96 can be obtained for coiling radius of 165 mm and 160 W with M^2 of 1.38 for 52 mm. The corresponding slope efficiencies are 60% and 48%. With smaller coiling radius, the brightness is 3.4 times as high as that of the larger one.展开更多
基金National Key Basic Research Project of China,the Shanghai Science & Technology Foundation(No.04DZ05120,05DZ22001)the Knowledge Innovation Project of Chinese Academy of Sciences.
文摘Coiling technique is used to control the transverse mode of a large-mode-area （LMA） multimode fiber laser. By winding the fiber to a coil with different radius, high-order modes of a multimode fiber laser are suppressed one by one and finally 15.4-W single-transverse-mode output is achieved when the coil radius is 20 mm. It is found that as the coil radius decreases, the beam quality of a multimode fiber laser gets better but the slope efficiency drops for higher-order modes are discriminated. During the experiment, as the coil radius of multimode fiber changes, output characteristic of the laser has been measured. Meanwhile, the mode loss of different modes is calculated theoretically. It is proved that the experimental measured results fit well with the theoretically calculated results.
基金This work was supported by the National Key Basic Research Project,Shanghai Science & Technology Foundation (No.04D205120,05D22001)Knowledge Innovation Project of the Chinese Academy of Sciences
文摘Coiling technique is used to suppress high-order modes of a large mode area （LMA） double clapt multimode fiber. Output powers and beam quality factors M^2 are measured under two different coiling radii. 217 W with M^2 of 2.96 can be obtained for coiling radius of 165 mm and 160 W with M^2 of 1.38 for 52 mm. The corresponding slope efficiencies are 60% and 48%. With smaller coiling radius, the brightness is 3.4 times as high as that of the larger one.
