Article
Optics
Julian Fischer, Jakub Drs, Norbert Modsching, Francois Labaye, Valentin J. Wittwer, Thomas Suedmeyer
Summary: The study presents an efficient Kerr-lens mode-locked thin-disk laser oscillator generating high peak power and average power pulses of 52 fs. This laser has a high optical-to-optical efficiency and delivers more than six times higher average power compared to 50 fs-class lasers.
Article
Engineering, Electrical & Electronic
Tao Wang, Bo Ren, Can Li, Jian Wu, Rongtao Su, Pengfei Ma, Zhi-Chao Luo, Pu Zhou
Summary: An experimentally demonstrated high-energy Mamyshev oscillator using an all polarization-maintaining 10/125 fiber configuration has shown excellent long-term stability and high output power at low repetition rates.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Optics
Wenlong Tian, Rui Xu, Li Zheng, Xuan Tian, Dacheng Zhang, Xiaodong Xu, Jiangfeng Zhu, Jun Xu, Zhiyi Wei
Summary: This study presents a high-power pure Kerr-lens mode-locked Yb:CALYO laser based on a dual-confocal cavity, delivering sub-100-fs pulses and achieving the highest average power reported for a Kerr-lens mode-locked Yb-bulk oscillator. Analysis of the dual-confocal cavity suggests a pathway to higher average power in the future for Kerr-lens mode-locked bulk lasers.
Article
Optics
Guolong Li, Chunyang Ma, Jie Peng, Jun Liu, Chujun Zhao, Pinghua Tang
Summary: In this study, the sub-100 fs Dy3+: fluoride fiber laser generation beyond 3 mu m regime was investigated numerically using a hybrid mode-locking mechanism based on the semiconductor saturable absorber mirror (SESAM) and the nonlinear polarization rotation (NPR) method. Compared with single SESAM and NPR-based mode-locking, the hybrid mode-locked Dy3+: fluoride fiber laser delivered much shorter pulses through fast and slow mode-locking from the NPR and SESAM, respectively. By considering dispersion compensation, an ultrafast pulse of 94 fs with a time-bandwidth product (TBP) of 0.333 was achieved. In addition, laser performance optimizations were investigated, and the shortest pulse duration of 85 fs was obtained. These results provide a feasible solution and design guidelines for ultrafast mid-infrared fiber laser generation beyond 3 mu m.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Optics
Li Wang, Weidong Chen, Zhongben Pan, Pavel Loiko, Ji Eun Bae, Fabian Rotermund, Xavier Mateos, Uwe Griebner, Valentin Petrov
Summary: We reported the first sub-100 fs mode-locked laser operation of a Tm:CLTGG crystal, using a single-walled carbon nanotube saturable absorber to achieve soliton mode-locking and obtain 69 fs pulses.
Article
Optics
Ruihong Dai, Nan Zhang, Yafei Meng, Zhenqiao Zhou, Fengqiu Wang
Summary: A compact and high-energy femtosecond fiber laser system based on CPA and SHG technology has been demonstrated, capable of generating high-energy, short-pulse laser with tunable wavelength. The system ensures pulse width of about 100 fs and sufficient pulse energy over the entire tuning range, performing well in a two-photon microscope.
Review
Optics
Jakub Drs, Julian Fischer, Norbert Modsching, Francois Labaye, Michael Mueller, Valentin J. J. Wittwer, Thomas Sudmeyer
Summary: Thin-disk lasers (TDLs) are widely used for high-power continuous-wave industrial applications and have great potential for ultrafast laser oscillators. However, the development of TDL oscillators directly delivering high average power at ultrafast pulse duration is still ongoing. This review discusses the evolving trends, scientific applications, and prospects of TDL oscillators.
LASER & PHOTONICS REVIEWS
(2023)
Article
Optics
Qinglin Sui, Shangming Ou, Yun Chen, Nan Zhang, Huanhuan Liu, Perry Ping Shum, Menglong Ma, Liang Guo, Qingmao Zhang
Summary: Supercontinuum generation using unamplified high-repetition-rate, sub-100 fs pulses with low pulse energy demonstrates superior noise performance and high acquisition speed. We present a novel gigahertz-repetition-rate, mode-locked Yb-doped fiber laser utilizing a hybrid mode-locking approach. The laser operates with a low initiating threshold of 300 mW and a broad mode-locking range of 600 mW (300-900 mW) in terms of pump power. It achieves a compressed pulse width of 95 fs and an output pulse energy of 92.9 pJ at a fundamental repetition rate of 1.15 GHz. The laser also offers switchable output polarization states with a polarization extinction ratio of 17.9 dB.
Article
Optics
Marin Hamrouni, Francois Labaye, Norbert Modsching, Valentin J. Wittwer, Thomas Sudmeyer
Summary: In this article, we present a directly diode-pumped high-power Kerr-lens mode-locked Yb:CALGO bulk laser oscillator operating at 1-GHz repetition rate. We report on two optimized laser configurations for either highest average power or shortest pulse duration, achieving the highest average power and shortest pulse duration for any GHz-class Yb-based laser oscillator. The compact laser setup, pumped by a low-cost multimode fiber-coupled laser diode, has a high potential as an economical yet powerful source for various applications.
Article
Optics
Yaodi Pi, Heng Wang, Yan Pan, Yun Shao, Yang Li, Jie Yang, Yichen Zhang, Wei Huang, Bingjie Xu
Summary: We demonstrated a sub-Mbps Gaussian-modulated coherent-state continuous-variable quantum key distribution system over a 100-km transmission distance. To control excess noise, the quantum signal and the pilot tone were co-transmitted in the fiber channel using wideband frequency and polarization multiplexing methods. A high-accuracy data-assisted time domain equalization algorithm was designed to compensate for phase noise and polarization variation. The experimentally calculated secure key rate over transmission distances of 50 km, 75 km, and 100 km was 7.55 Mbps, 1.87 Mbps, and 0.51 Mbps, respectively. This experiment significantly improved the transmission distance and secure key rate compared to previous state-of-the-art results, demonstrating the potential for long-distance and high-speed secure quantum key distribution.
Article
Optics
Jian-Cheng Zheng, Song Yang, Zhi-Wei Zhu, Kuen-Yao Lau, Li Li
Summary: We demonstrated an all-fiber Er-doped Mamyshev oscillator with short pulse duration and low mode-locking threshold based on an external seed. The experimental results suggest that the proposed laser shows potential applications in laser communication and biosensing fields.
OPTICS COMMUNICATIONS
(2022)
Article
Optics
Krishna Murari, Giovanni Cirmi, Hueseyin Cankaya, Gregory J. Stein, Benoit Debord, Frederic Gerome, Felix Ritzkosky, Fetah Benabid, Franz X. Kaertner
Summary: The limited gain bandwidth of laser crystals hampers the generation of few-cycle mid-infrared laser pulses beyond 2 µm without using an optical parametric chirped-pulse amplifier (OPCPA). To address this challenge, a two-stage nonlinear spectral broadening and pulse compression method based on a Kagome-type hollow-core photonic crystal fiber (HC-PCF) is utilized to compress picosecond pulses from a Ho:YLF amplifier to sub-50 fs duration at 2 µm wavelength. By fine-tuning the group delay dispersion (GDD), a compressed pulse of 48 fs is achieved, enabling the generation of white light for driving experiments in strong-field physics.
PHOTONICS RESEARCH
(2022)
Article
Optics
Usha Chakravarty, Avdhesh Kumar, Antony Kuruvilla, Aswin Asok, R. K. Jain, Rajpal Singh, Blacius Ekka, B. N. Upadhyaya, K. S. Bindra
Summary: We demonstrate a Thulium-doped fiber (TDF) laser oscillator with an all-fiber configuration, which achieves -117 W of continuous wave (CW) output power at -1940 nm with a slope efficiency of -53.8%. By optimizing the length of the gain fiber, stable CW output power at 1940 nm is obtained. The self-pulsing behavior in the longer length of the TDF is caused by the higher signal re-absorption near 1940 nm. Removing the self-pulses and proper thermal management enable the generation of more than -100 W of output power at -1940 nm. This all-fiber Tm-doped fiber laser shows promise for applications in the medical field and plastic welding.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Optics
Li Wang, Weidong Chen, Yongguang Zhao, Hanlin Yang, Wei Jing, Zhongben Pan, Hui Huang, Jiachen Liu, Ji Eun Bae, Fabian Rotermund, Pavel Loiko, Xavier Mateos, Zhengping Wang, Xinguang Xu, Uwe Griebner, Valentin Petrov
Summary: In this study, a power-scalable sub-100-fs laser in the 2-μm spectral range was achieved using a Tm3+-doped 'mixed' (Lu,Sc)(2)O-3 sesquioxide ceramic as an active medium. By employing single-walled carbon nanotubes as a saturable absorber, pulses as short as 58 fs at 2076 nm with an average output power of 114 mW were generated, representing a new achievement in the field of sub-100-fs mode-locked Tm lasers.
HIGH POWER LASER SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Electrical & Electronic
Suneui Park, Seyeon Yoo, Yuhwan Shin, Jeonghyun Lee, Jaehyouk Choi
Summary: This work introduces an ultralow-jitter injection-locked clock multiplier, achieving significant reduction in jitter through the use of power-gating injection method and a multi-functional calibrator.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2022)
Article
Optics
Arno Klenke, Albrecht Steinkopff, Christopher Aleshire, Cesar Jauregui, Stefan Kuhn, Johannes Nold, Christian Hupel, Sigrun Hein, Steffen Schulze, Nicoletta Haarlammert, Thomas Schreiber, Andreas Tuennermann, Jens Limpert
Summary: In this paper, a coherently combined femtosecond fiber chirped-pulse-amplification system based on a multicore fiber is presented, which demonstrates excellent performance in terms of high power and pulse energy. The system is scalable by increasing the number of cores in the fiber.
Article
Materials Science, Multidisciplinary
Paul Schmitt, Nadja Felde, Thorsten Dohring, Manfred Stollenwerk, Ingo Uschmann, Kevin Hanemann, Marie Siegler, Georg Klemm, Nancy Gratzke, Andreas Tunnermann, Stefan Schwinde, Sven Schroder, Adriana Szeghalmi
Summary: Metallic coatings, especially iridium, are crucial for infrared optical systems due to their high reflectivity and thermal stability. The properties of iridium coatings deposited by atomic layer deposition (ALD) and magnetron sputtering (MS) differ due to their different topography and microstructure.
OPTICAL MATERIALS EXPRESS
(2022)
Article
Optics
Tobias Heuermann, Ziyao Wang, Mathias Lenski, Martin Gebhardt, Christian Gaida, Mahmoud Abdelaal, Joachim Buldt, Michael Mueller, Arno Klenke, Jens Limpert
Summary: This study demonstrates a high-average-power, ultrafast, short-wavelength infrared laser system through the coherent combination of four ultrafast fiber amplifiers. The system achieves high peak power and stability. This result highlights the potential of coherent beam combining techniques for power scalability in the short-wavelength infrared spectral region.
Article
Chemistry, Physical
Jan Kinast, Andreas Tuennermann, Andreas Undisz
Summary: In this study, the thermal cycling stability of mirrors made of silicon particle reinforced aluminum compounds was investigated. It was found that the inclusion of silicon particles can enhance the dimensional stability of the mirrors under thermal loads, although it also induces thermal mismatch stresses and plastic deformation.
Article
Optics
Wilhelm Eschen, Lars Loetgering, Vittoria Schuster, Robert Klas, Alexander Kirsche, Lutz Berthold, Michael Steinert, Thomas Pertsch, Herbert Gross, Michael Krause, Jens Limpert, Jan Rothhardt
Summary: Microscopy with extreme ultraviolet radiation offers high-resolution imaging and excellent material contrast, making it ideal for studying complex structures and material composition.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Optics
Henning Stark, Christian Grebing, Joachim Buldt, Arno Klenke, Jens Limpert
Summary: In this study, the pulse-energy and peak-power limitations of a gas-filled multipass cell (MPC) for nonlinear pulse compression are surpassed by using a burst of four temporally separated pulses generated by two birefringent crystals. The burst is then spectrally broadened and recombined into a single pulse before compression. The use of the 4-pulse burst doubles the overall output energy supported by the MPC.
JOURNAL OF PHYSICS-PHOTONICS
(2022)
Article
Optics
P. Gierschke, C. Grebing, M. Abdelaal, M. Lenski, J. Buldt, Z. Wang, T. Heuermann, M. Mueller, M. Gebhardt, J. Rothhardt, J. Limpert
Summary: This article reports the generation of GW-class peak power 35-fs pulses at 2-μm wavelength. A compact, krypton-filled Herriott-type cavity with metallic mirrors is used for spectral broadening, enabling efficient post-compression. The results demonstrate excellent preservation of input beam quality and power transmission as high as 80%.
Review
Engineering, Electrical & Electronic
Arno Klenke, Cesar Jauregui, Albrecht Steinkopff, Christopher Aleshire, Jens Limpert
PROGRESS IN QUANTUM ELECTRONICS
(2022)
Article
Optics
Anne-Sophie Munser, Marcus Trost, Sven Schroeder, Martina Graf, Miriam A. Rosenbaum, Andreas Tuennermann
Summary: Due to its high sensitivity and quick measurement principle, angle-resolved scattering (ARS) measurements show promising potential as a rapid analysis tool for bacterial cells, especially at small sample sizes and low cell numbers. This study has demonstrated that scattered light from various bacterial cell samples can be analyzed at the single-cell level, which is a significant benefit compared to time-consuming conventional methods that require hours or days of cellular growth. With the proposed setup and data analysis method, it is possible to detect scatter differences among cell types as well as measure cell concentration.
Article
Optics
Mathias Lenski, Tobias Heuermann, Martin Gebhardt, Ziyao Wang, Christian Gaida, Cesar Jauregui, Jens Limpert
Summary: Investigation of the influence of the pump wavelength on high-power amplification of large-mode area, thulium-doped fibers suitable for ultrashort pulsed operation in the 2 μm wavelength region. Results show that pumping at 1692 nm achieves higher slope efficiency and average output power compared to pumping at 793 nm.
Article
Optics
Alexander Kirsche, Martin Gebhardt, Robert Klas, Lucas Eisenbach, Wilhelm Eschen, Joachim Buldt, Henning Stark, Jan Rothhardt, Jens Limpert
Summary: In this work, a continuously tunable extreme ultraviolet (XUV) source with a high photon flux spanning from 50 eV to 70 eV is presented. The setup includes a high-power fiber laser, a multipass cell, and a waveguide-based high harmonic generation setup. Tuning of the XUV spectrum is achieved by adjusting the laser's driving pulse energy and utilizing nonlinear propagation effects and pulse chirping. The method allows for high tuning speed and delivers reproducible and reliable results. A method for continuous, on-demand pulse-to-pulse switching of the generated XUV radiation with full spectral coverage is also proposed for future experiments.
Article
Optics
Maximilian Karst, Pauline Pfaller, Robert Klas, Ziyao Wang, Philipp Gierschke, Jan Rothhardt, Jens Limpert
Summary: This study presents the use of a gas-filled multipass cell to compress 515 nm wavelength second-harmonic pulses from a Yb:fiber laser from 240 fs to 15.7 fs. The system delivers 0.44 mJ of pulse energy, 22.4 W of average power at 50.8 kHz with an overall efficiency of more than 40%. These results demonstrate the capability of multipass-cell-based post-compression schemes to shift from the established near infrared region to the unexplored visible regime, enabling high efficiency generation of energetic ultrashort pulses at high repetition rates. The unique combination of parameters in the green spectral range offers immense potential for future development of high photon flux higher-order harmonic sources.
Article
Optics
Chang Liu, Wilhelm Eschen, Lars Loetgering, Daniel Penagos S. Molina, Robert Klas, Alexander Iliou, Michael Steinert, Sebastian Herkersdorf, Alexander Kirsche, Thomas Pertsch, Falk Hillmann, Jens Limpert, Jan Rothhardt
Summary: Table-top extreme ultraviolet (EUV) microscopy provides new possibilities for studying biological samples without using labels. In this study, we demonstrate ptychographic EUV imaging of dried, unstained model specimens, such as germlings of a fungus and bacteria cells, at a wavelength of 13.5 nm. By using a position-correlated ptychography approach, we achieve a millimeter-squared field of view with sub-60 nm spatial resolution, enabling the identification of nanoscale material composition inside the specimens. This work will advance EUV imaging applications and open up new possibilities in life science research.
Proceedings Paper
Optics
Christopher Aleshire, Albrecht Steinkopff, Maximilian Karst, Arno Klenke, Cesar Jauregui-Misas, Stefan Kuhn, Johannes Nold, Nicoletta Haarlammert, Thomas Schreiber, Jens Limpert
Summary: In-house fabricated Ytterbium-doped rod-type multicore fibers were used to generate and amplify ns-class pulses up to 37 mJ. Amplification was compared using tapered and untapered MCFs, with the tapered fiber improving beam quality while maintaining a large waveguide mode area for nonlinear effects suppression and increased amplification per unit length. These all-glass MCFs can facilitate energy and power scaling in compact high power coherently combined amplifier systems.
FIBER LASERS XIX: TECHNOLOGY AND SYSTEMS
(2022)
Proceedings Paper
Optics
Arno Klenke, A. Steinkopff, C. Aleshire, C. Jauregui, Stefan Kuhn, Johannes Nold, Christian Hupel, Sigrun Hein, Steffen Schulze, Nicoletta Haarlammert, Thomas Schreiber, Andreas Tuennermann, Jens Limpert
Summary: In this paper, a rod-type, Ytterbium-doped, multicore fiber with 4x4 cores is presented. This fiber is used in a CPA setup for coherent beam combination of femtosecond pulses. High average powers of up to 507 W after combination and compression are achieved at 10 MHz repetition rate. A high combination efficiency of 85% is realized together with excellent beam quality. Additionally, up to 600 µJ pulse energy is measured in a lower repetition rate configuration.
FIBER LASERS XIX: TECHNOLOGY AND SYSTEMS
(2022)
