基于氧化石墨烯/聚苯乙烯电光调制器的运转模式可切换光纤激光器  

Fiber Laser with Switchable Operating Modes Based on Graphene Oxide/Polystyrene Electro-Optic Modulator

作　　者：张晓颖 常建华[1,2] 戴腾飞 苏友朋 刘向 倪海彬 Zhang Xiaoying;Chang Jianhua;Dai Tengfei;Su Youpeng;Liu Xiang;Ni Haibin(School of Electronics&Information Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;Collaborative Innovation Center of Atmospheric Environment and Equipment Technology,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China)

机构地区：[1]南京信息工程大学电子与信息工程学院,江苏南京210044 [2]南京信息工程大学江苏省大气环境与装备技术协同创新中心,江苏南京210044

出　　处：《光学学报》2023年第2期133-142,共10页Acta Optica Sinica

基　　金：国家自然科学基金(61875089,62175114)。

摘　　要：利用电信号改变氧化石墨烯(GO)固有的光学吸收特性,可以实现对光纤锁模激光器输出性能的有效调控。在GO中引入聚苯乙烯(PS)纳米微球可以实现光波导结构,进而形成局域场并有效降低器件损耗。因此,采用微电子打印工艺制备了基于GO/PS的电光调制器,并以较低的泵浦功率(34.3 mW)实现了环形光纤激光器运转模式的主动调控。在0~20 V的调制电压下,激光器实现了连续波、调Q锁模、锁模三种运转模式的切换。所设计的全光纤电调制器件将锁模信号的脉冲宽度压缩到了20 ps,对应的重复频率为21.4 MHz。通过调控驱动电压,该器件的插入损耗从2.30 dB降低到了0.86 dB,平均输出功率从1.09 mW提升了1.52 mW。Objective Short-pulse fiber lasers have attracted great interest in numerous fields,including fiber communication,laser medical treatment,bioengineering,and material processing,owing to their compact structure,high efficiency,and robust stability.Physically,mode locking is an effective method to obtain ultrashort pulses,and it can be divided into active mode locking and passive mode locking.Passive mode locking based on saturable absorbers(SAs)has been widely studied.Among the SA materials,two-dimensional(2D)materials,such as graphene,black phosphorus,and molybdenum disulfide(MoS_(2)),are promising candidates due to their distinctive nonlinear saturable absorption ability,ultrafast recovery rate,and low cost.Plenty of passively mode-locked fiber lasers based on 2D materials have been developed to achieve different operating modes,such as continuous wave,Q-switched mode locking,and continuous wave mode locking by changing the pump power.However,due to the relatively fixed optical absorption characteristics of 2D materials,switchable operating modes of a mode-locked laser system are difficult to achieve without external modulation.The present study reports a novel kind of electro-optic modulator that is composed of graphene oxide(GO)and polystyrene(PS)microspheres and exhibits adjustable absorption characteristics under the action of an external electric field.The designed modulator,with a high optical transmission capability,enables electrically modulated fiber lasers to be switched among various operating modes,including continuous wave,Q-switched mode locking,and continuous wave mode locking.The proposed basic strategy and findings are expected to facilitate the design of new switchable ultrashort-pulse lasers based on electro-optic modulators.Methods The GO/PS all-fiber capacitive device is mainly prepared on a quartz substrate by the microelectronic printing process,and the main preparation process is presented in Fig.1.Improving the modulation efficiency of the device requires a straightforward,low-cost,and e

关 键 词：激光器 光纤锁模激光器 电光调制器 模式切换 氧化石墨烯 聚苯乙烯 

分 类 号：TN242[电子电信—物理电子学]