中国物理B ›› 2015, Vol. 24 ›› Issue (10): 104210-104210.doi: 10.1088/1674-1056/24/10/104210

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Analysis of gain distribution in cladding-pumped thulium-doped fiber laser and optical feedback inhibition problem in fiber-bulk laser system

吉恩才, 柳强, 胡震岳, 巩马理   

  1. State Key Laboratory of Precision Measurement Technology and Instruments, Center for Photonics and Electronics, Department of Precision Instrument, Tsinghua University, Beijing 100084, China
  • 收稿日期:2015-05-31 修回日期:2015-06-24 出版日期:2015-10-05 发布日期:2015-10-05
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant No. 61275146), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120002110066), and the Special Program of the Co-construction with Beijing Municipal Government of China (Grant No. 20121000302).

Analysis of gain distribution in cladding-pumped thulium-doped fiber laser and optical feedback inhibition problem in fiber-bulk laser system

Ji En-Cai (吉恩才), Liu Qiang (柳强), Hu Zhen-Yue (胡震岳), Gong Ma-Li (巩马理)   

  1. State Key Laboratory of Precision Measurement Technology and Instruments, Center for Photonics and Electronics, Department of Precision Instrument, Tsinghua University, Beijing 100084, China
  • Received:2015-05-31 Revised:2015-06-24 Online:2015-10-05 Published:2015-10-05
  • Contact: Liu Qiang E-mail:qiangliu@mail.tsinghua.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant No. 61275146), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120002110066), and the Special Program of the Co-construction with Beijing Municipal Government of China (Grant No. 20121000302).

摘要:

The steady-state gain distribution in cladding pumped thulium-doped fiber laser (TDFL) is analytically and numerically solved based on the rate equations including loss coefficients and cross relaxation effect. With the gain curve, a problem, which is named optical feedback inhibition (OFI) and always occurs in tandem TDFL-Ho:YAG laser system, is analyzed quantitatively. The actual characteristics of output spectra and power basically prove the conclusion of theoretical analysis. Then a simple mirror-deflected L-shaped cavity is employed to restrain the external feedback and simplify the structure of fiber-bulk Ho:YAG laser. Finally, 25 W of 2097-nm laser power and 51.2% of optical-to-optical conversion efficiency are obtained, and the beam quality factor is less than 1.43 obtained by knife-edge method.

关键词: thulium-doped fiber laser, gain distribution, optical feedback inhibition, Ho:YAG laser

Abstract:

The steady-state gain distribution in cladding pumped thulium-doped fiber laser (TDFL) is analytically and numerically solved based on the rate equations including loss coefficients and cross relaxation effect. With the gain curve, a problem, which is named optical feedback inhibition (OFI) and always occurs in tandem TDFL-Ho:YAG laser system, is analyzed quantitatively. The actual characteristics of output spectra and power basically prove the conclusion of theoretical analysis. Then a simple mirror-deflected L-shaped cavity is employed to restrain the external feedback and simplify the structure of fiber-bulk Ho:YAG laser. Finally, 25 W of 2097-nm laser power and 51.2% of optical-to-optical conversion efficiency are obtained, and the beam quality factor is less than 1.43 obtained by knife-edge method.

Key words: thulium-doped fiber laser, gain distribution, optical feedback inhibition, Ho:YAG laser

中图分类号:  (Fiber lasers)

  • 42.55.Wd
42.55.Rz (Doped-insulator lasers and other solid state lasers) 42.60.Mi (Dynamical laser instabilities; noisy laser behavior)