Femtosecond mode-locking of a fiber laser using a CoSb3-skutterudite-based saturable absorber
We experimentally demonstrate an ultrafast mode-locker based on a CoSb3 skutterudite topological insulator for femtosecond mode-locking of a fiber laser. The mode-locker was implemented on a side-polished fiber platform by depositing a CoSb3/PVA composite. The measured modulation depth and saturation power for the transverse-electric mode input were ～5% and ～8.7 W, respectively, and ～2.8% and ～10.6 W for the transverse-magnetic mode input. By incorporating this mode-locker into an erbium-doped fiber-based ring cavity, we were able to readily generate mode-locked, soliton pulses having a pulse width of ～833 fs at 1557.9 nm. The 3-dB bandwidth of the output pulses and time-bandwidth product were ～3.44 and 0.353 nm, respectively. To the best of the authors’ knowledge, this is the first demonstration of the use of a skutterudite-based saturable absorber for femtosecond mode-locked pulse generation.
基金项目：National Research Foundation of Korea (NRF)10.13039/501100003725 (2018R1A2B6001641); Institute for Information and Communications Technology Promotion (IITP-2018-2015-0-00385).
Yoontaek Kim：School of Electrical and Computer Engineering, University of Seoul, Seoul 02504, South Korea
Kyungtaek Lee：School of Electrical and Computer Engineering, University of Seoul, Seoul 02504, South Korea
Ju Han Lee：School of Electrical and Computer Engineering, University of Seoul, Seoul 02504, South Korea
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Jinho Lee, Yoontaek Kim, Kyungtaek Lee, and Ju Han Lee, "Femtosecond mode-locking of a fiber laser using a CoSb3-skutterudite-based saturable absorber," Photonics Research 6(10), C36 (2018)