Abstract
We present a scheme of fiber-connector-type carbon-nanotube-based saturable absorber (CNT-SA) with enhanced thermal damage threshold, in which the CNTs are deposited on the fiber connector end in a ring pattern for evanescent-field interaction instead of direct interaction. The thermal damage threshold of such CNT-SA is found to be increased by around 130% compared with an evenly deposited one. An all-fiber Fabry-Perot (FP) linear cavity passively mode-locked laser is further constructed incorporating the prepared CNT-SA, where the optical power is confined in a relatively short laser cavity to investigate the thermal damage threshold and the performance of the CNT-SA. Stable output pulses with a fundamental repetition rate of 211.84 MHz and a pulse width of 680 fs are generated from the fiber laser. The mode-locking operation can be maintained an intra-cavity average power of 30 mW, indicating that the CNT-SA can withstand a relatively high optical power without performance degradation.
Highlights
Mode-locked fiber lasers using carbon-nanotube-based saturable absorbers (CNTSAs) have attracted much research interest due to their potential applications for ultra-short pulse generation with simple cavity structures [1,2,3,4,5]
We present a scheme of fiber-connector-type carbon-nanotubebased saturable absorber (CNT-SA) with enhanced thermal damage threshold, in which the CNTs are deposited on the fiber connector end in a ring pattern for evanescent-field interaction instead of direct interaction
The thermal damage threshold of such CNT-SA is found to be increased by around 130% compared with an evenly deposited one
Summary
Mode-locked fiber lasers using carbon-nanotube-based saturable absorbers (CNTSAs) have attracted much research interest due to their potential applications for ultra-short pulse generation with simple cavity structures [1,2,3,4,5]. The conventional method to construct a CNT-SA can be deposited CNT layers or CNT-polymer films sandwiched between fiber ferrule connectors or fiber ends [6,7,8,9] In such schemes, the central part of the optical field which carries the majority of power can effectively interact with the deposited CNTs. one concern of these schemes is the relatively low thermal damage threshold. Since the oxidation is prevented by the surrounded nitrogen gas, such CNT-SA can operate at a high power level without deterioration These methods incorporate extra materials as well as gas sealing which lose the basic simplicity advantage of CNT-SAs. In this paper, we propose and demonstrate a scheme of fiber-connector-type CNT-SA with enhanced thermal damage threshold. The developed shortcavity mode-locked fiber laser shows a stable operation at a maximum pump power of 240 mW with a corresponding intra-cavity average power higher than 30 mW, suggesting that the CNT-SA can withstand a relatively high optical power without performance degradation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
