1 上海大学特种光纤与光接入网重点实验室,上海先进通信与数据科学研究院,特种光纤与先进通信国际合作联合实验室,上海 200444
2 中国计量科学研究院,北京 100029
3 华中科技大学光学与电子信息学院下一代互联网接入系统国家工程实验室,湖北 武汉 430074
4 东莞理工学院电信工程与智能化学院,广东 东莞 523808
5 华东师范大学精密光谱科学与技术国家重点实验室,上海 200062
6 浙江省引力波精密测量重点实验室国科大杭州高等研究院,浙江 杭州 310024
利用45°倾斜光纤光栅(45°-TFG)作为光纤型起偏器,搭建了一台高可靠性高稳定性的掺铒锁模光纤激光器,并以此为基础实现了重复频率和载波包络偏移频率的精确锁定。当泵浦功率为228 mW时,基于45°-TFG的锁模激光振荡器可实现3 dB光谱带宽为60.4 nm、脉冲宽度为68 fs的超短脉冲输出,在12 h内功率的均方根稳定性达到0.033%,且在较大的泵浦范围内均能维持较好的展宽锁模状态。经过自主搭建的非线性脉冲放大、超连续谱产生以及自参考拍频干涉光路,获得了信噪比为32 dB的信号。最后通过搭建基于锁相环的主动反馈控制电路,将和信号溯源至一台GPS时频系统,最终测得和信号归一化后在1 s门时间内频率稳定度为2.38×10-12和6.41×10-16。这是首次实现基于45°-TFG的光纤激光频率梳,表明了基于45°-TFG的锁模光纤激光器在实际应用中的潜力。
锁模光纤激光器 光纤光栅 非线性偏振旋转 光纤激光频率梳 激光与光电子学进展
2024, 61(1): 0106005
Author Affiliations
Abstract
1 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences (CAS), Xi’an 710119, China
2 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
3 College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Silicon waveguides typically exhibit optical anisotropy, which leads to polarization correlation and single-polarization operations. This consequently creates a demand for polarization-control devices. This paper introduces a CMOS-compatible O-band reconfigurable TE/TM polarization rotator comprising two symmetrical polarization rotator–splitters and phase shifters. This configuration enables dynamic conversion of any linear polarization to its quadratic equivalent. Experimental results indicate that the reconfigurable polarization rotator exhibits an insertion loss of less than 1.5 dB. Furthermore, the bandwidth for a polarization extinction ratio beyond 15 dB exceeds 60 nm.
silicon-based optoelectronics polarization rotation polarization switch Chinese Optics Letters
2024, 22(1): 011303
光学 精密工程
2023, 31(23): 3395
强激光与粒子束
2023, 35(10): 101002
Author Affiliations
Abstract
1 Shanghai University, Shanghai Institute for Advanced Communication and Data Science, Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communications, Shanghai, China
2 Aston University, Aston Institute of Photonic Technologies, Birmingham, United Kingdom
3 Huazhong University of Science and Technology, School of Optical and Electronic Information and NGIA, Wuhan, China
Breathing solitons, i.e., dynamic dissipative solitons with oscillating pulse shape and energy caused by different mechanisms of spatiotemporal instabilities, have received considerable interest from the aspects of nonlinear science and potential applications. However, by far, the study of breathing solitons is still limited within the time scale of hundreds of cavity round trips, which ignores the slow dynamics. To fill this lacuna, we theoretically investigate a new type of vector dissipative soliton breathing regime and experimentally demonstrate this concept using mode-locked fiber lasers, which arise from the desynchronization of orthogonal states of polarization (SOPs) in the form of complex oscillations of the phase difference between the states. The dynamic evolution of polarization states of the vector breathings solitons takes the form of a trajectory connecting two quasi-equilibrium orthogonal SOPs on the surface of the Poincaré sphere. The dwelling time near each state is on the scale of a tenth of a thousand cavity round trip times that equals the breathing period, which is up to 2 orders of magnitude longer than that for common breathers. The obtained results can reveal concepts in nonlinear science and may unlock approaches to the flexible manipulation of laser waveforms toward various applications in spectroscopy and metrology.
dissipative solitons polarization dynamics vector soliton breather Q-switched mode locking nonlinear polarization rotation coupled oscillators Advanced Photonics Nexus
2023, 2(6): 066007
1 长春理工大学 光电工程学院 空间光电技术研究所,吉林 长春 130022
2 长春理工大学 光电工程学院 光学工程系,吉林 长春 130022
基于无波分裂脉冲产生的平坦超连续谱被报道。笔者采用非线性偏振旋转(NPR)作为锁模方法来实现耗散孤子脉冲和无波分裂脉冲的切换输出。在0.3 W的泵浦功率下,获得了耗散孤子脉冲。脉冲宽度为5.8 ps,脉冲间隔为54 ns,与11.05 m的腔长一致,信噪比为55 dB,压缩后的脉冲宽度为0.61 ps。值功率可以被提升到1.18 kW。通过适当调整腔偏振态和增加泵浦功率,耗散孤子可以演化为无波分裂脉冲。随着泵浦功率的提高,脉冲宽度从11.7 ps增加到20.2 ps,几乎增加了两倍。经过计算,时间带宽积从23.9增加到53.43。较大的啁啾可以抵抗非线性相移的影响,从而避免脉冲分裂。无波分裂脉冲的脉冲能量可以提高到3.89 nJ,是耗散孤子脉冲能量的五倍。随后,使用耗散孤子和无波分裂脉冲作为种子源去获得超连续谱。结果表明,在锥形高非线性光纤中,无波分裂脉冲产生的超连续谱范围和平坦度均优于耗散孤子脉冲。基于耗散孤子脉冲和无波分裂脉冲产生的超连续谱范围为1 400~2 000 nm,覆盖了S波段、C波段、L波段三个主要通信波段,20 dB带宽分别为310.3 nm和426.4 nm。这项工作将有助于高能量脉冲光纤激光器的发展,并提高其在超连续谱产生和光通信领域的潜在应用。
超连续谱 非线性偏振旋转 耗散孤子 无波分裂脉冲 平坦度 supercontinuum nonlinear polarization rotation dissipative soliton wave-free breaking pulse flatness 红外与激光工程
2023, 52(5): 20220745
红外与激光工程
2023, 52(5): 20220609
Author Affiliations
Abstract
1 Center for Optics Research and Engineering, Key Laboratory of Laser & Infrared System, Ministry of Education, Shandong University, Qingdao 266237, China
2 School of Information Science and Engineering, Shandong Provincial Key Laboratory of Laser Technology and Application, Shandong University, Qingdao 266237, China
Based on the Nd-doped single-mode fiber as the gain medium, an all-fiber 12th harmonic mode-locked (HML) laser operating at the 0.9 µm waveband was obtained for the first time, to the best of our knowledge. A mandrel with a diameter of 10 mm was employed to introduce bending losses to suppress mode competition at 1.06 µm, which resulted in a suppression ratio of up to 54 dB. The 1st–12th order HML pulses with the tunable repetition rate of 494.62 kHz–5.94 MHz were obtained in the mode-locked laser with a center wavelength of . In addition, the laser has an extremely low threshold pump power of 88 mW. To the best of our knowledge, this is the first time that an HML pulse has been achieved in a 0.9 µm Nd-doped single-mode all-fiber mode-locked laser with the advantages of low cost, simple structure, and compactness, which could be an ideal light source for two-photon microscopy.
Nd-doped fiber laser harmonic mode-locking bending loss nonlinear polarization rotation low repetition rate Chinese Optics Letters
2023, 21(1): 011405
1 广东省特殊儿童发展与教育重点实验室,广东 湛江 524048
2 岭南师范学院物理科学与技术学院,广东 湛江 524048
糖度检测在生物、医疗等领域具有关键作用。为了提高旋光法测量糖溶液浓度的分辨率,本文提出利用正交反射镜消除偏振光被金属平面镜反射后的消旋光现象,建立了参考臂和测量臂信号的相位差与溶液浓度之间的函数关系,并研究了正交反射多次旋光效应。在不增加样品长度的前提下,通过多次旋光使分辨率倍增。以葡萄糖溶液为例,四次旋光的实验结果表明:在0~0.4690 g/mL范围内,浓度测量分辨率为8×10-6 g/mL,最大测量相对误差小于0.54%。正交反射多次旋光检测技术可以为血糖与自闭症发病机理研究提供实时在线血糖检测。
光谱学 旋光法 正交反射 多次旋光 葡萄糖浓度 激光与光电子学进展
2022, 59(21): 2130001