High Power Fiber Laser Technology

A special issue of Micromachines (ISSN 2072-666X). This special issue belongs to the section "E:Engineering and Technology".

Deadline for manuscript submissions: 30 November 2024 | Viewed by 7231

Special Issue Editors

Laser Fusion Research Center, China Academy of Engineering Physics, Chengdu 610200, China
Interests: high power fiber laser sources; mode instability; beam combination

E-Mail Website
Guest Editor
College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
Interests: high power fiber lasers; nonlinear effects in fiber laser and its application

Special Issue Information

Dear Colleagues,

As one of the first kinds of lasers to be demonstrated since the invention of the laser, fiber lasers have gained a solid reputation as versatile and powerful laser machining tools. With the parallel and rapid development of high-brightness laser diodes and double-cladding fiber materials, the output power of fiber lasers spanning a wide wavelength has seen an unprecedented increase, promising a new avenue for micromachining applications. One example is the combination of extremely high beam quality fiber lasers with 3D printing technology to fabricate complicated and compound components, and these applications require higher laser power for efficient operation. However, fiber lasers at a high-power level of several kilowatts now suffer from some problems, such as mode/polarization degradation, nonlinear effects, and thermal effects, which deteriorates the beam quality and has hampered the deep integration of high-power fiber lasers with micromachines, limiting their applications. To break through the aforementioned limitations, new high-power fiber laser technology, including the new fiber laser concept, new fiber design and materials, new fiber components, and new beam combination technology, should be proposed and encouraged, and laser–matter interaction with new types of fiber lasers should be explored. Accordingly, this Special Issue seeks to showcase research papers and review articles that focus on novel methodological developments in high-power fiber lasers, i.e., the concept and physics of novel fiber lasers, the design and manufacture of fiber materials, and the fabrication of high-performance fiber components.

Dr. Rumao Tao
Dr. Hanwei Zhang
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Micromachines is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • fiber laser
  • fiber amplifier
  • beam quality
  • mode stability
  • stimulated Raman effect
  • thermal effects
  • beam combination
  • beam control
  • laser beam propagation
  • laser–matter interaction

Published Papers (7 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

9 pages, 4377 KiB  
Communication
Study on Electrically Modulated Quasi-Continuous Wave Fe: ZnSe Solid-State Laser with Hundred-Hertz
by Yingchao Wan, Yanlong Shen, Ke Wang, Tongxing Chai, Yousheng Wang, Zhengge Chen and Feng Zhu
Micromachines 2023, 14(12), 2194; https://doi.org/10.3390/mi14122194 - 30 Nov 2023
Viewed by 703
Abstract
Iron-doped binary chalcogenide crystals are very promising for tunable solid-state lasers operating over the 3~5 μm spectral range. Fe: ZnSe is one of the most important gain crystals with the obvious advantages of material characteristics and conversion efficiency. By adjusting the output mode [...] Read more.
Iron-doped binary chalcogenide crystals are very promising for tunable solid-state lasers operating over the 3~5 μm spectral range. Fe: ZnSe is one of the most important gain crystals with the obvious advantages of material characteristics and conversion efficiency. By adjusting the output mode of the pump source, an Fe: ZnSe laser can operate in two modes at liquid nitrogen temperatures: continuous wave (CW) and pulse output. In terms of CW output, the Fe: ZnSe laser obtained a maximum 2.63 W continuous power output which was confined to the power of the pump source. An optical-to-optical efficiency of 47.05% was acquired. Direct electrical modulation was applied to the pump source. The highest average power of the quasi-CW laser, whose central wavelength is 4.02 μm, has a value of 253 mW with an optical-to-optical efficiency of 42.88% and a full width at half maximum (FWHM) of 23 nm when the pulse frequency is 100 Hz of 10% duty factor. The output waveform is consistent with the modulation waveform applied to the pump source. We report to the first of our knowledge an electrically modulated quasi-CW Fe: ZnSe laser in the pulse regime, equipped with features of compactness in structure, ignoring additional modulators, convenience in control, high efficiency, and sustainable operation, of great interest for solving numerous scientific and applied problems. Full article
(This article belongs to the Special Issue High Power Fiber Laser Technology)
Show Figures

Figure 1

15 pages, 6006 KiB  
Article
Improving Plasticity of Ferritic Stainless Steel Welded Joints via Laser Spot Control
by Lidong Gu, Qi Tang, Yanqing Li, Fengde Liu and Piyao Liu
Micromachines 2023, 14(11), 2072; https://doi.org/10.3390/mi14112072 - 8 Nov 2023
Viewed by 728
Abstract
The plasticity of welded 441 ferritic stainless steel joints was controlled by varying the laser beam spot diameter during laser welding. A stainless steel plate thickness of 1.2 mm was used. The microstructures of the welded joints were analyzed for various spot diameters. [...] Read more.
The plasticity of welded 441 ferritic stainless steel joints was controlled by varying the laser beam spot diameter during laser welding. A stainless steel plate thickness of 1.2 mm was used. The microstructures of the welded joints were analyzed for various spot diameters. The elongation of breaks and the reduced area of tensile specimens were analyzed to study the effects of spot diameter on plasticity of the welded joints. The results showed that the weld melt width and weld column crystal size increased with the spot diameter, but isometric crystals in the center of the weld were gradually reduced. Increasing spot diameter resulted in decreased tensile strength, elongation after breaks, and area reduction. So the parameter must be controlled during the laser welding. Full article
(This article belongs to the Special Issue High Power Fiber Laser Technology)
Show Figures

Figure 1

18 pages, 2927 KiB  
Article
An Exploratory Study of Laser Scribing Quality through Cross-Section Scribing Profiles
by Ruqi Chen, Shing Chang and Shuting Lei
Micromachines 2023, 14(11), 2020; https://doi.org/10.3390/mi14112020 - 30 Oct 2023
Viewed by 1020
Abstract
This article presents a novel approach for evaluating laser scribing quality through cross-section profiles generated from a three-dimensional optical profiler. Existing methods for assessing scribing quality only consider the width and depth of a scribe profile. The proposed method uses a cubic spline [...] Read more.
This article presents a novel approach for evaluating laser scribing quality through cross-section profiles generated from a three-dimensional optical profiler. Existing methods for assessing scribing quality only consider the width and depth of a scribe profile. The proposed method uses a cubic spline model for cross-section profiles. Two quality characteristics are proposed to assess scribing accuracy and consistency. Accuracy is measured by the ratio of the actual laser-scribed area to the target area (RA), which reflects the deviation from the desired profile. The mean square error (MSE) is a measure of how close each scribed cross-section under the same scribing conditions is to the fitted cubic spline model. Over 1370 cross-section profiles were generated under 171 scribing conditions. Two response surface polynomial models for RA and MSE were built with 18 scribing conditions with acceptable scribing depth and RA values. Both RA and MSE were considered simultaneously via contour plots. A scatter plot of RA and MSE was then used for Pareto optimization. It was found that the cross-sectional profile of a laser scribe could be accurately represented by a cubic spline model. A multivariate nonlinear regression model for RA and MSE identified pulse energy and repetition rate as the two dominant laser parameters. A Pareto optimization analysis further established a Pareto front, where the best compromised solution could be found. Full article
(This article belongs to the Special Issue High Power Fiber Laser Technology)
Show Figures

Figure 1

12 pages, 2017 KiB  
Article
Spectral Failsafe System of High-Power Laser Using Dual Fiber Bragg Gratings
by Zhaoyu Zong, Xiaocheng Tian, Mengqiu Fan, Dandan Zhou, Rui Zhang, Junpu Zhao, Wanguo Zheng and Dangpeng Xu
Micromachines 2023, 14(10), 1927; https://doi.org/10.3390/mi14101927 - 14 Oct 2023
Viewed by 823
Abstract
Phase-modulated (PM) spectral failsafe systems are necessary to promptly terminate amplification processes following accidental seeding of a high-power laser chain with a non-PM pulse to prevent optical damage. In this work, we present a reliable spectral failsafe system that can indicate the presence [...] Read more.
Phase-modulated (PM) spectral failsafe systems are necessary to promptly terminate amplification processes following accidental seeding of a high-power laser chain with a non-PM pulse to prevent optical damage. In this work, we present a reliable spectral failsafe system that can indicate the presence or absence of sufficient PM light. This requirement is met by combining dual temperature-sensitive fiber Bragg gratings detection with high-speed RF amplitude comparisons. The failsafe trigger signal is generated when the spectral power at the peak sideband exceeds that at the center. The spectral failsafe system has the ability to distinguish between adequate and inadequate PM pulses, and it exhibits significant robustness in pulse width, TEC temperature drift, and DFB wavelength drift in experiments, making it valuable for safe high-power laser operations and providing a useful reference for other detection system designs. Full article
(This article belongs to the Special Issue High Power Fiber Laser Technology)
Show Figures

Figure 1

13 pages, 4964 KiB  
Article
Multiple Bound State Soliton Pulses in the All Polarization Maintaining Fiber Laser
by Dalin Sun, Qi Zhao, Shaowen Chu, Chunyu Cao, Jihong Pei, Xintong Xu and Shuangchen Ruan
Micromachines 2023, 14(8), 1528; https://doi.org/10.3390/mi14081528 - 29 Jul 2023
Viewed by 1038
Abstract
The bound state soliton pulse, a novel mode-locked output state of fiber lasers, has been studied extensively to gain a better understanding of soliton interactions and to explain the mechanism behind the generation of mode-locked pulses. In this particular research, we utilized a [...] Read more.
The bound state soliton pulse, a novel mode-locked output state of fiber lasers, has been studied extensively to gain a better understanding of soliton interactions and to explain the mechanism behind the generation of mode-locked pulses. In this particular research, we utilized a self-made saturable absorber (SA) consisting of single-walled carbon nanotubes (SWCNT) in a fully polarization maintaining (PM) erbium-doped fiber optical path. Through this setup, we observed various bound state pulse phenomena, including the double bound state with different phase differences, the bound state formed by two double pulse bound states, the multi-pulse bound state, etc. The abundant bound soliton pulse states demonstrated the excellent nonlinear absorption characteristics of the SA as well as the excellent optical properties of the all-PM fiber laser. It contributed to exploring the relationship between sub pulses and mode-locked pulses in the future. Additionally, due to the strong interaction between bound state solitons and the inherent stability of the PM optical path, there was potential for utilizing this setup as a seed source to enhance the stability of high-power fiber lasers. Full article
(This article belongs to the Special Issue High Power Fiber Laser Technology)
Show Figures

Figure 1

8 pages, 2434 KiB  
Article
Influence of Pump Current Waveform on The Mitigation of Transverse Mode Instability in Fiber Laser Oscillator
by Junyu Chai, Wenguang Liu, Xiaolin Wang, Qiong Zhou, Jiangbin Zhang, Hanwei Zhang, Pengfei Liu, Yao Lu, Dan Zhang, Zongfu Jiang and Guomin Zhao
Micromachines 2023, 14(4), 864; https://doi.org/10.3390/mi14040864 - 17 Apr 2023
Cited by 1 | Viewed by 1106
Abstract
We carry out a detailed investigation of TMI mitigation by pump modulation based on multiple current waveforms in a fiber laser oscillator. Compared with continuous wave (CW), the modulation of various waveforms, including sinusoidal wave, triangular wave, and pulse wave with a duty [...] Read more.
We carry out a detailed investigation of TMI mitigation by pump modulation based on multiple current waveforms in a fiber laser oscillator. Compared with continuous wave (CW), the modulation of various waveforms, including sinusoidal wave, triangular wave, and pulse wave with a duty cycle of 50% and 60%, can increase the TMI threshold. The average output power of a stabilized beam is boosted via the adjustment of phase difference between the signal channels. The TMI threshold is increased to 270 W under a modulation of pulse wave (duty cycle: 60%) with a phase difference of 440 μs, where the beam quality is 1.45. This threshold can be further improved by adding groups of pump LDs and drivers, which is a promising approach for beam stabilization of high-power fiber lasers. Full article
(This article belongs to the Special Issue High Power Fiber Laser Technology)
Show Figures

Figure 1

Review

Jump to: Research

22 pages, 8382 KiB  
Review
Research Progress in Tunable Fiber Lasers Based on Multimode Interference Filters
by Liqiang Zhang, Kexin Zhu, Yicun Yao, Xiuying Tian, Hailong Xu and Zhaogang Nie
Micromachines 2023, 14(11), 2026; https://doi.org/10.3390/mi14112026 - 30 Oct 2023
Viewed by 913
Abstract
Tunable fiber lasers have the advantages of good beam quality, high integration, and adjustable output wavelength, and they are widely used in fields such as optical fiber communication and optical fiber sensing. The fiber filter is one of the key components of tunable [...] Read more.
Tunable fiber lasers have the advantages of good beam quality, high integration, and adjustable output wavelength, and they are widely used in fields such as optical fiber communication and optical fiber sensing. The fiber filter is one of the key components of tunable fiber lasers. Among the various filters currently used, multimode interference filters have the advantages of simple structure, convenient implementation, flexible tuning methods, and convenient spectral range design. The structures of multimode interference filters based on multimode fibers, no-core fibers, multi-core fibers, tapered fibers, and other special fibers are introduced in this paper. The working principles and tuning methods are analyzed and the research progress of tunable fiber lasers based on these filters is summarized. Finally, the development trend of tunable fiber lasers based on multimode interference filters is discussed. The rapid development and applications of multimode interference filters can help improve the performance of continuous and pulse lasers as well as promote the practicality of tunable fiber lasers. Full article
(This article belongs to the Special Issue High Power Fiber Laser Technology)
Show Figures

Figure 1

Back to TopTop