Solution processed graphene based saturable absorber for mode-locked ultrafast fiber laser

• Main Authors: Wen, Chih-Yuan, 溫智元
• Other Authors: Hsieh, Wen-Feng
• Format: Others
• Language: en_US
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/50566723276445482244

碩士 === 國立交通大學 === 顯示科技研究所 === 104 === In this thesis, we obtained high-quality graphene flakes produced by liquid-phase exfoliation method under 2 hours ultrasonic time to fabricate graphene/PVA composite and directly coated graphene-film on fiber end as saturable absorbers for passively mode-locking Er-doped fiber lasers. We found graphene/PVA saturable absorbers cannot sustain high pumping power owing to the heat accumulation in PVA results in increasing intra cavity loss to cause unlock of the laser. On the other hand, graphene-film on fiber end can sustain much higher pumping power over 350 mW. Finally, we demonstrated passively mode-locked ultrafast Er-doped fiber laser with a maximal output power of 15.4 mW at central wavelength of 1557 nm and pulse duration of 823.5 fs using graphene-film as a saturable absorber.