Supercontinuum Generation from a Thulium Ultrafast Fiber Laser in a High NA Silica Fiber
Document Type
Article
Publication Title
IEEE Photonics Technology Letters
Publication Date
6-24-2017
Abstract
A broadband supercontinuum is generated from a thulium ultrafast soliton fiber laser in a high numerical aperture silica fiber with low nJ seed pulse energies. Amplification of a thulium based ultrafast soliton ring fiber laser in two customized thulium doped fiber amplifiers provides pulses varying in energy between 1.8 nJ and 13.5 nJ. Coupling these seed pulses into a high numerical aperture silica fiber UHNA 7 of varying length, a systematic study of the impact of pulse energy, pulse duration and nonlinear fiber length is conducted. Based on the normal dispersion, self-phase modulation dominates for lower pump power values and results in a symmetric spectral broadening process. For higher pulse energies, four-wave mixing and Raman scattering contribute to a strong red-shift of the spectrum beyond 2.3~\mu \text{m}. For a fiber length of 20 m of UHNA 7, a broadband supercontinuum spanning from 1.7~\mu \text{m} to 2.33~\mu \text{m} is generated with a 20 dB spectral bandwidth of 502 nm with an output pulse energy of 4.4 nJ, corresponding to an output power of 92 mW. This represents a low seed energy threshold for efficient flat supercontinuum generation at infrared wavelengths.
Volume
31
Issue
22
First Page
1787
Last Page
1790
DOI
10.1109/LPT.2019.2946835
Recommended Citation
Zeng, J., Akosman, A., & Sander, M. (2017). Supercontinuum Generation from a Thulium Ultrafast Fiber Laser in a High NA Silica Fiber. IEEE Photonics Technology Letters, 31 (22), 1787-1790. https://doi.org/10.1109/LPT.2019.2946835
ISSN
10411135
E-ISSN
19410174