Author Affiliations
Abstract
1 Shenzhen Key Laboratory of Laser Engineering, Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
2 Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
3 College of Physics and Energy, Shenzhen University, Shenzhen 518060, China
The pulse energy in the ultrafast soliton fiber laser oscillators is usually limited by the well-known wave-breaking phenomenon owing to the absence of a desirable real saturable absorber (SA) with high power tolerance and large modulation depth. Here, we report a type of microfiber-based MoTe2 SA fabricated by the magnetron-sputtering deposition (MSD) method. High-energy wave-breaking free soliton pulses were generated with pulse duration/pulse energy/average output power of 229 fs/2.14 nJ/57 mW in the 1.5 μm regime and 1.3 ps/13.8 nJ/212 mW in the 2 μm regime, respectively. To our knowledge, the generated soliton pulses at 1.5 μm had the shortest pulse duration and the highest output power among the reported erbium-doped fiber lasers mode locked by transition metal dichalcogenides. Moreover, this was the first demonstration of a MoTe2-based SA in fiber lasers in the 2 μm regime, and the pulse energy/output power are the highest in the reported thulium-doped fiber lasers mode locked by two-dimensional materials. Our results suggest that a microfiber-based MoTe2 SA could be used as an excellent photonic device for ultrafast pulse generation, and the MSD technique opens a promising route to produce a high-performance SA with high power tolerance and large modulation depth, which are beneficial for high-energy wave-breaking free pulse generation.
Lasers, fiber Mode-locked lasers Ultrafast lasers Nonlinear optical materials Photonics Research
2018, 6(6): 06000535
盐城工学院电气工程学院, 江苏 盐城 224051
为获得连续可调谐高频微波信号,设计了一种基于单片机控制的高精度热电制冷器(TEC)温度 控制系统。该系统的控制芯片采用MSP430F149单片机,通过温度传感器TMP112进行温度信息的采集,驱 动电路产生的脉宽调制(PWM)波信号驱动TEC芯片进行温度控制,稳态误差约为0.06 °C。利用该温度控制器 控制光纤的温度,通过调节温度获得了10.872~10.905 GHz的高频微波信号,信号频移大小的斜率为1.1 MHz/°C。 增加控制系统的温度调谐范围可获得更宽调谐范围的微波信号。
温度控制 热电制冷器 布里渊频移 微波信号 temperature control thermoelectric cooler Brillouin frequency shift microwave signal