Author Affiliations
Abstract
School of Physics and Astronomy, Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai, China
Spatiotemporal mode-locking creates great opportunity for pulse energy scaling and nonlinear optics research in fiber. Until now, spatiotemporal mode-locking has only been realized in normal-dispersion dissipative soliton and similariton fiber lasers. In this paper, we demonstrated the first experimental realization of a spatiotemporally mode-locked soliton laser in mid-infrared fluoride fiber with anomalous dispersion. The mode-locked fluoride fiber oscillator directly generated a record pulse energy of 16.1 nJ and peak power of 74.6 kW at 2.8 μm wavelength. This work extends the spatiotemporal mode-locking to soliton fiber lasers and should have a wide interest for the laser community.
mid-infrared soliton fiber laser spatiotemporal mode-locking High Power Laser Science and Engineering
2023, 11(5): 05000e59
Author Affiliations
Abstract
1 Key Laboratory for Laser Plasmas (MOE), Collaborative Innovation Center of IFSA, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, China
2 Joint Laboratory of High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
3 Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai, China
In strong-field physics experiments with ultraintense lasers, a single-shot cross-correlator (SSCC) is essential for fast optimization of the pulse contrast and meaningful comparison with theory for each pulse shot. To simultaneously characterize an ultrashort pulse and its long pedestal, the SSCC device must have both a high resolution and a large temporal window. However, the resolution and window in all kinds of single-shot measurement contradict each other in principle. Here we propose and demonstrate a novel SSCC device with two separate measurement channels: channel-1 for the large-window pedestal measurement has a moderate resolution but a large window, while channel-2 for the ultrashort pulse measurement has a small window but a high resolution; this allows the accurate characterization of the pulse contrast in a single shot. A two-channel SSCC device with a 200-fs resolution and 114-ps window has been developed and tested for its application in ultraintense lasers at 800 nm.
pulse contrast single-shot cross-correlator ultrashort ultraintense laser High Power Laser Science and Engineering
2022, 10(6): 06000e43
Author Affiliations
Abstract
School of Physics and Astronomy, Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai, China
We report on a grating-free fiber chirped pulse amplifier (CPA) at 2.8 μm for the first time. The CPA system adopted Er:ZBLAN fiber with large anomalous dispersion as the stretcher and germanium (Ge) rods as the compressor with a compact structure. High-energy picosecond pulses of 2.07 μJ were generated at the repetition rate of 100 kHz. Using highly dispersive Ge rods, the amplified pulses were compressed to 408 fs with a pulse energy of 0.57 μJ, resulting in a peak power of approximately 1.4 MW. A spectral broadening phenomenon in the main amplifier was observed, which was caused by the special gain shape of the Er:ZBLAN fiber amplifier in operation and confirmed by our numerical simulation. This compact fiber CPA system at 2.8 μm will be practical and meaningful for application fields.
Er:ZBLAN fiber fiber chirped pulse amplifier grating free mid-infrared High Power Laser Science and Engineering
2022, 10(6): 06000e41
Author Affiliations
Abstract
1 School of Physics and Astronomy, Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai200240, China
2 School of Information and Electrical Engineering, Hebei University of Engineering, Handan056038, China
Dissipative solitons have been realized in mode-locked fiber lasers in the theoretical framework of the Ginzburg–Landau equation and have significantly improved the pulse energy and peak power levels of such lasers. It is interesting to explore whether dissipative solitons exist in optical parametric oscillators in the framework of three-wave coupling equations in order to substantially increase the performance of optical parametric oscillators. Here, we demonstrate a temporal-filtering dissipative soliton in a synchronously pumped optical parametric oscillator. The temporal-gain filtering of the pump pulse combined with strong cascading nonlinearity and dispersion in the optical parametric oscillator enables the generation of a broad spectrum with a nearly linear chirp; consequently, a significantly compressed pulse and high peak power can be realized after dechirping outside the cavity. Furthermore, we realized, for the first time, dissipative solitons in an optical system with a negative nonlinear phase shift and anomalous dispersion, extending the parameter region of dissipative solitons. The findings may open a new research block for dissipative solitons and provide new opportunities for mid-infrared ultrafast science.
cascading nonlinearity dissipative solitons optical parametric oscillators temporal filtering High Power Laser Science and Engineering
2022, 10(2): 02000e16
1 上海交通大学物理与天文学院激光等离子体教育部重点实验室,上海 200240
2 上海交通大学IFSA协同创新中心,上海 200240
理论和实验研究了一种2.8 μm Er∶ZBLAN光纤孤子自压缩放大器。 放大器采用锁模Er∶ZBLAN光纤振荡器作为种子源,锁模脉冲宽度为240 fs,峰值功率为16.9 kW,重复频率为54.3 MHz。通过单级孤子自压缩放大,实验获得了脉冲宽度为110 fs、峰值功率达151 kW的中红外飞秒脉冲输出。
激光器 超快激光器 锁模激光器 激光放大器 红外和远红外激光器
Author Affiliations
Abstract
1 School of Physics and Astronomy, Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
2 Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
3 SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology, and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
Optical vortex is a promising candidate for capacity scaling in next-generation optical communications. The generation of multi-vortex beams is of great importance for vortex-based optical communications. Traditional approaches for generating multi-vortex beams are passive, unscalable and cumbersome. Here, we propose and demonstrate a multi-vortex laser, an active approach for creating multi-vortex beams directly at the source. By printing a specially-designed concentric-rings pattern on the cavity mirror, multi-vortex beams are generated directly from the laser. Spatially, the generated multi-vortex beams are decomposable and coaxial. Temporally, the multi-vortex beams can be simultaneously self-mode-locked, and each vortex component carries pulses with GHz-level repetition rate. Utilizing these distinct spatial-temporal characteristics, we demonstrate that the multi-vortex laser can be spatially and temporally encoded for data transmission, showing the potential of the developed multi-vortex laser in optical communications. The demonstrations may open up new perspectives for diverse applications enabled by the multi-vortex laser.
红外与激光工程
2020, 49(12): 20201060
Author Affiliations
Abstract
School of Physics and Astronomy, Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
We demonstrated a femtosecond mode-locked Er:ZrF4-BaF2-LaF3-AlF3-NaF (Er:ZBLAN) fiber laser at 2.8 μm based on the nonlinear polarization rotation technique. The laser generated an average output power of 317 mW with a repetition rate of 107 MHz and pulse duration as short as 131 fs. To the best of our knowledge, this is the shortest pulse generated directly from a mid-infrared mode-locked Er:ZBLAN fiber laser to date. Numerical simulation and experimental results confirm that reducing the gain fiber length is an effective way to shorten the mode-locked pulse duration in the Er:ZBLAN fiber laser. The work takes an important step towards sub-100-fs mid-infrared pulse generation from mode-locked Er:ZBLAN fiber lasers.
generation mode-locked pulses Er:ZBLAN fiber Chinese Optics Letters
2020, 18(3): 031402
Zhipeng Qin 1,2,3Guoqiang Xie 1,2,3,*Hongan Gu 1,2,3Ting Hai 1,2,3[ ... ]Liejia Qian 1,2,3,*
Author Affiliations
Abstract
1 Shanghai Jiao Tong University, School of Physics and Astronomy, Shanghai, China
2 Shanghai Jiao Tong University, Collaborative Innovation Center of Inertial Fusion Sciences and Applications, Shanghai, China
3 Shanghai Jiao Tong University, Key Laboratory for Laser Plasmas, Ministry of Education, Shanghai, China
The mode-locked fluoride fiber laser (MLFFL) is an exciting platform for directly generating ultrashort pulses in the mid-infrared (mid-IR). However, owing to difficulty in managing the dispersion in fluoride fiber lasers, MLFFLs are restricted to the soliton regime, hindering pulse-energy scaling. We overcame the problem of dispersion management by utilizing the huge normal dispersion generated near the absorption edge of an infrared-bandgap semiconductor and promoted MLFFL from soliton to breathing-pulse mode-locking. In the breathing-pulse regime, the accumulated nonlinear phase shift can be significantly reduced in the cavity, and the pulse-energy-limitation effect is mitigated. The breathing-pulse MLFFL directly produced a pulse energy of 9.3 nJ and pulse duration of 215 fs, with a record peak power of 43.3 kW at 2.8 μm. Our work paves the way for the pulse-energy and peak-power scaling of mid-IR fluoride fiber lasers, enabling a wide range of applications.
ultrafast fiber laser mid-infrared breathing pulse mode-locking dispersion management Advanced Photonics
2019, 1(6): 065001
Author Affiliations
Abstract
1 Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation Centre of IFSA (CICIFSA), School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
2 Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
High-power femtosecond lasers beyond $5~\unicode[STIX]{x03BC}\text{m}$ are attractive for strong-field physics with mid-infrared (IR) fields but are difficult to scale up. In optical parametric chirped-pulse amplification (OPCPA) at mid-IR wavelengths, a nonlinear crystal is vital, and its transmittance, dispersion, nonlinear coefficient and size determine the achievable power and wavelength. OPCPA beyond $5~\unicode[STIX]{x03BC}\text{m}$ routinely relies on semiconductor crystals because common oxide crystals are not transparent in this spectral range. However, the small size and low damage threshold of semiconductor crystals fundamentally limit the peak power to gigawatts. In this paper, we design a terawatt-class OPCPA system at $5.2~\unicode[STIX]{x03BC}\text{m}$ based on a new kind of oxide crystal of $\text{La}_{3}\text{Ga}_{5.5}\text{Nb}_{0.5}\text{O}_{14}$ (LGN). The extended transparent range, high damage threshold, superior phase-matching characteristics and large size of LGN enable the generation of 0.13 TW seven-cycle pulses at $5.2~\unicode[STIX]{x03BC}\text{m}$. This design fully relies on the state-of-the-art OPCPA technology of an octave-spanning ultrafast Ti:sapphire laser and a thin-disk Yb:YAG laser, offering the performance characteristics of high power, a high repetition rate and a stable carrier–envelope phase.
few-cycle mid-infrared OPCPA oxide LGN crystals High Power Laser Science and Engineering
2019, 7(4): 04000e61