Liu H H, Yang Y, Chow K K
School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Opt Express. 2013 Aug 12;21(16):18975-82. doi: 10.1364/OE.21.018975.
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.
我们提出了一种具有提高的热损伤阈值的光纤连接器型碳纳米管基可饱和吸收体（CNT-SA）方案，其中碳纳米管以环形图案沉积在光纤连接器端部，用于倏逝场相互作用而非直接相互作用。发现这种CNT-SA的热损伤阈值与均匀沉积的相比提高了约130%。进一步构建了一个全光纤法布里-珀罗（FP）线性腔被动锁模激光器，其中结合了制备的CNT-SA，光功率被限制在相对较短的激光腔内，以研究热损伤阈值和CNT-SA的性能。光纤激光器产生了稳定的输出脉冲，其基频重复率为211.84 MHz，脉冲宽度为680 fs。在腔内平均功率为30 mW时锁模操作仍可维持，这表明CNT-SA能够承受相对较高的光功率而性能不退化。
