Author Affiliations
Abstract
1 State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, National Photoelectric Technology and Functional Materials & Application International Cooperation Center, Institute of Photonics & Photon-Technology, Northwest University, Xi’an 710069, China
2 e-mail: xmcheng@nwu.edu.cn
3 e-mail: rzy@nwu.edu.cn
Graphene microfibers are burgeoning modulators with great potential in all-optical communication. One of the critical issues that remains to be understood is the dynamic mechanism of light–graphene interaction. Here, we propose a power dependent modulation by using 980 nm pump light and 1064 nm signal light via graphene microfiber, and the results show a strong transmission reduction and frequency blue shift with the increase of pump power. The experimental observation is attributed to a stimulated Brillouin scattering process induced by the pump light. Power and frequency variations are a result of energy transition of the scattered phonon in the fiber. This work reveals the nonlinear effect process in the light–graphene interaction and provides a new method for power and frequency control with graphene all-optical modulation.
Photonics Research
2019, 7(1): 01000008
Author Affiliations
Abstract
1 Institute of Photonics and Photon-Technology, National Key Laboratory of Photoelectric Technology and Functional Materials (Culture Base), Northwest University, Xi’an 710069, China
2 Shaanxi Engineering Technology Research Center for Solid State Lasers and Application, Xi’an 710069, China
We report a double Q-switched 946 nm laser with a magnesium-oxide-doped LiNbO3 (MgO:LN) electro-optic (EO) crystal and a monolayer molybdenum diselenide (MoSe2) saturable absorber (SA). A pulsed laser diode side-pumped long neodymium-doped yttrium aluminum garnet rod (φ3×65 mm) is used as the gain medium. Large pulse energy up to 3.15 mJ and peak power up to 346 kW are generated at the repetition rate of 550 Hz, corresponding to the beam quality factors of Mx2=3.849, My2=3.868. Monolayer MoSe2 nanosheets applied in the experiment would be a promising SA for a passive Q-switching operation.
140.3580 Lasers, solid-state 140.3540 Lasers, Q-switched 160.4236 Nanomaterials Chinese Optics Letters
2018, 16(3): 031402
Yang Bai 1,2,3,†Bing Bai 1,2,3Diao Li 1,2,3Yanxiao Sun 1,2,3[ ... ]Jintao Bai 1,2,3
Author Affiliations
Abstract
1 National Key Laboratory of Photoelectric Technology and Functional Materials (Culture Base), Institute of Photonics and Photon-Technology, Northwest University, Xi’an 710069, China
2 Shaanxi Engineering Technology Research Center for Solid State Lasers and Application, Xi’an 710069, China
3 Provincial Key Laboratory of Photo-electronic Technology, Institute of Photonics and Photon-Technology, Northwest University, Xi’an 710069, China
We report a cavity-dumped 1123 nm laser with narrow pulse width and high peak power by an MgO: LN crystal electro-optic (EO) modulator. Based on the structural optimization design of a folded biconcave cavity using the 808 nm pulsed laser diode (LD) side-pumped ceramic Nd: YAG rod, output pulses with maximum pulse energy and peak power up to 39.6 mJ and 9.73 MW were obtained, corresponding to 100 Hz repetition rate and 4.07 ns pulse width. The instabilities of pulse width and pulse energy were $\pm$1.55% and $\pm$2.06%, respectively. At the highest repetition rate of 1 kHz, the pulse energy, pulse width, and peak power were 11.3 mJ, 5.05 ns, and 2.24 MW, respectively. The instabilities of pulse width and pulse energy were $\pm$2.65% and $\pm$3.47%, respectively.
cavity-dumped high peak power MgO: LN EO 1123?nm laser short pulse width High Power Laser Science and Engineering
2018, 6(1): 010000e4
上海工程技术大学 电子电气学院, 上海 201620
为了研究机械应力对石英滤波输出的影响,基于石英晶体的弹光效应,推导了石英晶体双折射率与不同方向机械应力之间的关系,并进行了数值模拟.采用了Ultra-6600系列紫外-可见分光光度计搭建了实验系统,得到了立奥型石英双折射滤光片的透射光谱图,并对光谱图进行了研究与分析.结果表明,在不同方向机械应力作用下,立奥型石英双折射滤光片的中心波长发生漂移;大小为0.0025N/m2机械应力沿Ox1轴、Ox2轴、Ox3轴方向作用,石英滤波片中心波长向长波长方向的漂移量分别约为0.4nm,0.6nm,1nm.这一结果对石英双折射滤光片的封装制作、正确设计和使用是有帮助的.
光学器件 晶体光学 机械应力 弹光效应 石英晶体双折射滤光片 optical devices crystal optics mechanical stress elasto-optical effect quratz crystal birefringent filter
上海工程技术大学 电子电气工程学院, 上海 201620
为了更准确地研究温度对光纤Lyot型消偏器消偏性能的影响,根据参考文献中光纤消偏器的结构参量,使用保偏光纤熔接机等制作完成了光纤Lyot消偏器,在全温条件(-40℃～80℃)下,其偏振度P≤0.5%;同时搭建了恒温和变温条件下消偏器输出偏振度测试系统,并分析了偏振度改变产生的原因。结果表明,温度恒定在不同值时(-40℃和80℃),消偏器的输出偏振度基本保持不变;当温度按一定梯度升高或者降低时,消偏器的输出偏振度会随之改变。这对于光纤传感应用的研究具有一定的参考价值。
光纤光学 光纤Lyot消偏器 偏振度 温度 温度梯度 fiber optics fiber Lyot depolarizer degree of polarization temperature temperature gradient
1 西北大学 光子学与光子技术研究所, 物理学院, 西安 710069
2 陕西省光电技术与功能材料省部共建国家重点实验室培育基地, 国家级光电技术与纳米功能材料国际联合研究中心, 西安 710069
将石墨烯作为宽带可饱和吸收体分别应用在1.06 μm Nd∶YAG固体激光器、2μm Tm∶YAP固体激光器以及1.55 μm掺铒全光纤激光中.石墨烯采用化学汽相沉积法制备, 以乙炔作为碳源, 25 μm厚的铜箔作为生长基体和催化剂, H2为载气, Ar为辅助气体, 在常压、1 000 ℃高温条件下进行生长.1.06 μm Nd∶YAG固体激光器实验中, 采用直线型侧面泵浦腔型结构, 当输出功率为10 W时, 得到了重复频率为360 kHz, 脉冲宽度240 ns的最短脉冲输出, 其单脉冲能量为27 μJ, 峰值功率为115.7 W; 2 μm Tm∶YAP固体激光器实验中, 使用中心波长在795 nm附近的半导体激光器作为泵浦源, 采用10%透过率的输出镜获得了脉宽为1.4 μs的最窄调Q脉冲; 环形腔1.55 μm掺铒全光纤激光器实验中, 利用1.25 m长的高掺铒光纤作为增益光纤, 当泵浦功率为100 mW时, 输出功率为10 mW, 获得了脉冲宽度314 ps的稳定被动连续锁模脉冲, 脉冲重复频率为20 MHz并验证了同次制备的石墨烯的宽带可饱和吸收特性.
石墨烯 可饱和吸收体 被动调Q 被动锁模 短脉冲 Graphene Fiber laser Passively Q-switched Saturable absorber Short pulses
李雕 1,2,3,*江曼 1,2,3祁媚 1,2,3郑新亮 1,2,3[ ... ]白晋涛 1,2,3
1 西北大学 光子学与光子技术研究所
2 陕西省光电技术与功能材料省部共建国家重点实验室培育基地
3 国家级光电技术与功能材料及应用国际科技合作基地，西安 710069
4 剑桥大学 工程学院,英国 剑桥 CB3 0FA
5 中国科学院西安光学精密机械研究所 瞬态光学与光子技术国家重点实验室,西安 710119
报道了石墨烯可饱和吸收体作用于2 μm激光的被动调Q脉冲输出特性.采用线型谐振腔，掺铥光纤和石墨烯可饱和吸收镜分别作为增益介质和被动调Q器件，792 nm半导体激光器端面泵浦掺铥光纤，利用一组准直聚焦透镜将腔内光束会聚到石墨烯所在位置，成功实现了中心波长为1 958 nm的被动调Q脉冲输出.当泵浦功率为3.0 W时，获得了1.02 μs的最窄脉冲宽度，对应的平均输出功率为26 mW，脉冲重复频率为116 kHz，单脉冲能量为224 nJ，平均输出功率、脉冲宽度与泵浦功率近似呈线性关系.实验结果表明，石墨烯优良的可饱和吸收特性，可有效实现2 μm波段的被动调Q激光运转.
石墨烯 被动调Q 掺铥光纤 可饱和吸收体 短脉冲 Graphene Passively Qswitched Tm doped fiber Saturable absorber Short pulses
