Article
Engineering, Mechanical
Junyuan Huang, Yingchun Guan, Seeram Ramakrishna
Summary: The tribological behavior of femtosecond laser-textured leaded brass samples was studied under different surface roughness and lubrication conditions. The coefficient of friction exhibited consistent changes under various lubrication conditions, with the roughness affecting the friction coefficient. The wear mechanisms were mainly adhesive wear and abrasive wear, with differences in specific wear mechanisms observed under various friction conditions.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Optics
Dongshi Zhang, Xinzhuo Li, Yao Fu, Qinghe Yao, Zhuguo Li, Koji Sugioka
Summary: This work reveals that fluid dynamics induced by femtosecond laser ablation in liquid can break the laser polarization state restriction and produce irregular circular-LIPSS and crisscross-LIPSS. Liquid vortex plays a crucial role in the formation of macropores and complex fluid dynamics on mountain-like microstructures can cause the formation of CCLIPSS. This opens up new possibilities to diversify the morphologies of LIPSS formed by femtosecond laser ablation in liquid.
OPTO-ELECTRONIC ADVANCES
(2022)
Article
Physics, Multidisciplinary
Chenhao Li, Hongtao Liang, Yang Yang, Zhiyong Yu, Xin Zhang, Xiangming Ma, Wenliang Lu, Zhenrong Sun, Ya Cheng
Summary: Through two-temperature model molecular-dynamics simulations, ultrafast modulation of the pure molten metal surface stress fields under single femtosecond laser pulse irradiation is predicted. The dynamic surface tensions are sharply modulated within picoseconds after irradiation, due to the development of nanometer scale non-hydrostatic regime behind the liquid surfaces' exterior atomic layer.
CHINESE PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Xiaojie Li, Xin Li, Lan Jiang, Pei Zuo, Yang Zhao, Sumei Wang, Xiaozhe Chen, Misheng Liang, Le Ma
Summary: This study introduces a new method for preparing twin graphene quantum dots by electric-field-assisted temporally-shaped femtosecond laser ablation liquid, achieving control over the crystallinity of GQDs and potential applications in the fields of magnetism, spin transport, or photoluminescence.
Article
Materials Science, Multidisciplinary
Xiangjing Guo, Haiying Song, Yachao Li, Peng Wang, Shibing Liu
Summary: In this paper, a colloidal solution of silicon carbide (SiC) nanoparticles is obtained using femtosecond laser ablation. The nanoparticles are spherical and uniform in size with an average diameter of 2.84 nm. The crystal structure of the nanoparticles is confirmed to be 4H-SiC. The colloidal solution exhibits strong absorption in the ultraviolet region and the SiC nanoparticles show reverse saturation absorption characteristics.
Article
Optics
Marie -Pier Lord, Michel Olivier, Martin Bernier, Real Vallee
Summary: Femtosecond fiber lasers have been a game changer in laser technology industry, providing high brightness ultrashort pulses in compact, affordable, and reliable setups. This study presents the first femtosecond fiber laser operating in the visible spectrum, expanding the range of applications for such sources. The all-normal dispersion regime passively mode-locked ring cavity is based on nonlinear polarization evolution in a single-mode Pr3+-doped fluoride fiber. The compressed pulses at 635 nm have a duration of 168 fs, a peak power of 0.73 kW, and a repetition rate of 137 MHz.
Article
Optics
Sungkwon Shin, Woojin Lee, Jong Kab Park, Doh-Hoon Kim
Summary: This paper presents a femtosecond laser processing method to precisely control taper angles of micro-holes. The ablation depth depends on the ablation rate, number of repetitions for scanning, beam size, and spot overlap ratio, which in turn influence the taper angles. We developed a multilevel material processing method involving analytical models to achieve desired taper angles on 64FeNi alloy sheets.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Materials Science, Ceramics
Aida Naghilou, Oscar Bomati-Miguel, Ana Subotic, Ruth Lahoz, Markus Kitzler-Zeiler, Christine Radtke, Miguel A. Rodriguez, Wolfgang Kautek
Summary: This study focused on the generation of bimetallic oxide nanoparticles using a reaction-sintering method and laser ablation in liquids. The results showed successful production of nanoparticles without a core-shell morphology, influenced by the properties of metallic oxide ceramics and the liquid used. The research lays the groundwork for the creation of well-defined bimetallic nanoparticles with potential X-ray and magnetic absorption properties for multimodal imaging applications.
CERAMICS INTERNATIONAL
(2021)
Article
Optics
Keiichi Bamoto, Haruyuki Sakurai, Shuntaro Tani, Yohei Kobayashi
Summary: This study demonstrated the use of Bayesian optimization as an efficient method to find the optimal conditions for laser processing. It showed that the optimum set of parameters to achieve a desired shape can be obtained autonomously and more than an order of magnitude faster than with a simple grid-search.
Article
Optics
Alan T. K. Godfrey, Deepak L. N. Kallepalli, Sabaa Rashid, Jesse Ratte, Chunmei Zhang, P. B. Corkum
Summary: This study presents a novel method for controlling blister formation in Laser-Induced Forward Transfer (LIFT) by using a thin metal film between two polymer films. The laser energy deposition is primarily in the metal layer, and blister expansion is driven by laser-induced spallation of the gold film.
Review
Chemistry, Analytical
Matteo Calvarese, Tobias Meyer-Zedler, Michael Schmitt, Orlando Guntinas-Lichius, Juergen Popp
Summary: In this article, recent developments and advances in femtosecond laser ablation, particularly in the field of biomedical applications, are reviewed. The focus has shifted towards expanding the use of ultrafast laser ablation in various fields beyond ophthalmology, such as dental and orthopaedic surgery. The integration of spectroscopic analytical imaging techniques and the development of endoscopic probes for ultrafast laser surgery have paved the way for clinical applications in otolaryngology, inner ear surgery, as well as cancer detection and simultaneous tumor removal.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2023)
Article
Optics
Wang Xue, Mingxuan Yang, Yingchun Guan, Jiapeng Bi, Xinuo Zhang, Yimeng Wang, Hai Yong
Summary: Orthopedic diseases are a growing concern for human health, and traditional mechanical osteotomy poses risks due to mechanical and thermal damages. Femtosecond lasers offer a safe and efficient method for laminectomy. This study used femtosecond laser ablation aided by convolutional neural network and collaborative control, analyzing the spectral composition and temperature distribution during the process. The findings suggest that a power of 15W with cooling is the optimal parameter to prevent carbonization.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Optics
John Lopez, Samba Niane, Guillaume Bonamis, Pierre Balage, Eric Audouard, Clemens Honninger, Eric Mottay, Inka Manek-Honninger
Summary: This article reports for the first time on the top-down percussion drilling of high-quality deep holes in different glasses using femtosecond laser pulses in GHz-burst mode. The dynamics of the drilling process are revealed through pump-probe shadowgraphy and thermal camera imaging, showing that the drilling process in GHz-burst mode is fundamentally different from single-pulse processing and confirming the presence of thermal accumulation.
Article
Optics
Feng Yang, Zhigang Dong, Renke Kang, Cheng Liu, Dongjiang Wu, Guangyi Ma
Summary: Reaction-bonded silicon carbide composites exhibit a complex ablation mechanism under femtosecond laser irradiation. The ablation threshold decreases with increasing pulse number and stabilizes. Photochemical ablation dominates at low fluence and low pulse number, while photothermal ablation dominates at higher fluence and pulse number. A preliminary model of the ablation mechanism was established based on surface morphology, microstructure, and physical phase analysis.
Article
Optics
Hasnaa Meliani, Mohamed Assoul, Michael Fontaine, Vahan Malkhasyan, Alexandre Gilbin, Guy Monteil
Summary: The femtosecond laser-matter interaction with tungsten carbide containing 10% cobalt was investigated, resulting in the production of laser-induced periodic surface structures (LIPSS) with specific spatial period and amplitude. By studying the athermal ablation threshold of tungsten carbide and other parameters, dimples were fabricated without any thermal effects.
Article
Optics
M. E. Shaheen, J. E. Gagnon, B. J. Fryer
LASER PHYSICS LETTERS
(2015)
Article
Spectroscopy
M. E. Shaheen, J. E. Gagnon, B. J. Fryer
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2015)
Article
Optics
M. E. Shaheen, J. E. Gagnon, B. J. Fryer
Article
Geochemistry & Geophysics
Mikkel Tetland, John Greenough, Brian Fryer, Michael Hinds, Mohamed E. Shaheen
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2017)
Article
Physics, Atomic, Molecular & Chemical
M. E. Shaheen, J. E. Gagnon, B. J. Fryer, A. Polat
INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
(2017)
Article
Polymer Science
Mohamed E. Shaheen, Ahmed R. Ghazy, El-Refaie Kenawy, Farouk El-Mekawy
Article
Physics, Applied
Mohamed E. Shaheen, Joel E. Gagnon, Brian J. Fryer
LASER AND PARTICLE BEAMS
(2019)
Article
Optics
M. E. Shaheen, J. E. Gagnon, B. J. Fryer
OPTICS AND LASERS IN ENGINEERING
(2019)
Article
Optics
Mohamed E. Shaheen, Ahmed R. Ghazy, El-Refaie Kenawy, Riyad A. Ghazy, Farouk El-Mekawy
Article
Physics, Multidisciplinary
M. E. Shaheen, J. E. Gagnon, B. J. Fryer
Summary: The study investigated the laser ablation behavior of alumina ceramics and the effects of laser parameters on ablation rate. No changes in the structure and chemical composition of alumina were observed. The ablation threshold fluence was found to be 1.35 J/cm².
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Geosciences, Multidisciplinary
John D. Greenough, Alejandro Velasquez, Mohamed E. Shaheen, Joel Gagnon, Brian J. Fryer, Mikkel Tetland, Yuan Chen, David Mossman
Summary: Trace elements in native gold provide unique fingerprints for individual gold deposits, allowing for distinguishing gold sources and understanding geochemical processes during gold deposit formation. The behavior of elements in native gold suggests that samples from Timmins deposits formed under similar but slightly variable geochemical conditions. The association of certain elements with gold in the deposits supports precipitation from hydrothermal fluids carrying the elements.
CANADIAN JOURNAL OF EARTH SCIENCES
(2021)
Article
Environmental Sciences
Mohamed E. Shaheen, Walid Tawfik, Asmaa F. Mankoula, Joel E. Gagnon, Brian J. Fryer, Farouk El-Mekawy
Summary: This study utilized LA-ICP-MS to determine the concentrations of heavy metals in agricultural soils of Kafr El-Zayat city and assess soil quality. The results indicated that some heavy metal concentrations exceeded global background values and Canadian soil quality guidelines, with a moderate contamination level observed in all sampling sites. Multivariate analysis revealed correlations and sources of heavy metals in agricultural soils, highlighting clustering patterns and principal component analysis explaining a significant portion of variance.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Optics
M. E. Shaheen, J. E. Gagnon, B. J. Fryer
Summary: This study investigates the interaction of the 193 nm ArF excimer laser with brass and fused silica in the ambient air. The study compares the differences in surface morphology and ablation rate of craters produced in brass and fused silica at different values of fluence and number of laser pulses using optical and scanning electron microscopy. The results show that the ablation rate is slightly lower in fused silica than in brass, and melting and ejection of molten material were dominant in the ablation of brass. Various shapes and sizes of particles were observed in the debris deposited around the craters created in both brass and fused silica.
Article
Environmental Sciences
Mohamed E. Shaheen, Walid Tawfik, Asmaa F. Mankola, Joel E. Gagnon, Brian J. Fryer, Farouk M. El-Mekawy
Summary: This study monitored the contamination levels of twelve heavy metals in agricultural soils using ICP-OES in Kafr El-Zayat city, Egypt. Various geochemical parameters were used to estimate contamination levels. The results showed that the majority of soil samples had moderate contamination levels and different sources of pollution were identified through cluster analysis and principal component analysis.
SOIL & SEDIMENT CONTAMINATION
(2023)
Article
Chemistry, Multidisciplinary
Asmaa F. Mankoula, Walid Tawfik, Joel E. Gagnon, Brian J. Fryer, F. El-Mekawy, Mohamed E. Shaheen
Summary: The recent years have seen a significant increase in heavy metal contamination levels in agricultural soils, necessitating continuous evaluation to protect soil and human health.
EGYPTIAN JOURNAL OF CHEMISTRY
(2021)
