Article
Physics, Applied
Sophie E. Parsons, Ross E. Turner, Michael R. Armstrong, Harry B. Radousky, Javier E. Garay, Farhat N. Beg
Summary: In this study, a 100 ps laser was used to investigate the characteristics of the non-solid ablator and the impact of tamper materials on pressure generation and depth. The experiments showed that the sapphire tamper material achieved higher pressures at lower laser intensities compared to the coverslip glass tamper material. However, the current simulation methods require further physics to accurately predict the effects of tamper materials on pressure generation and depth.
APPLIED PHYSICS LETTERS
(2023)
Article
Nanoscience & Nanotechnology
John Linden, Neta Melech, Igor Sakaev, Ofer Fogel, Slava Krylov, David Nuttman, Zeev Zalevsky, Marina Sirota
Summary: This article presents a novel technology for precise fabrication of quartz resonators for MEMS applications. The approach is based on laser-induced chemical etching of quartz. The main steps include UV laser treatment of a Cr-Au-coated quartz wafer and wet etching. The fabricated devices show reduced surface roughness and improved wall profiles.
MICROSYSTEMS & NANOENGINEERING
(2023)
Article
Chemistry, Analytical
Wei Wang, Lanxiang Sun, Peng Zhang, Tong Chen, Liming Zheng, Lifeng Qi
Summary: The study found that matrix effects have different degrees of impact on the analysis line under different experimental parameters, and the impact of matrix effects can be reduced by adjusting the laser defocusing amount and spectrometer delay. Additionally, using the spectrum generated by the pure sample as the matrix background can reduce the interference of matrix effects.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2021)
Article
Nanoscience & Nanotechnology
Ziqian Ning, Yiling Lian, Lan Jiang, Jingya Sun, Shouyu Wu, Feifei Wang
Summary: This study demonstrates the anisotropic light-material interaction and nonlinear optical response of yttria-stabilized zirconia (YSZ) with fs laser-induced micro-/nanostructures on [100], [110], and [111] planes. The results show that the nonlinear absorption (NLA) of crack structures is significantly improved, particularly in [100] samples. This research provides a potential approach to enhance the nonlinearity of materials for the development of nonlinear devices using fs laser.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Optics
Mark C. Phillips, Elizabeth J. Kautz, Sivanandan S. Harilal
Summary: High-resolution tunable laser absorption spectroscopy is used to measure time-resolved absorption spectra for six neutral uranium transitions in a laser-produced plasma. Analysis of the spectra shows that kinetic temperatures are similar for all six transitions, but excitation temperatures are higher than kinetic temperatures from 10-100 microseconds, indicating departures from local thermodynamic equilibrium.
Article
Engineering, Aerospace
Liam Pieters, Ron Noomen
Summary: This research investigates the performance of a space-based laser system for removing debris objects smaller than 10 cm. The system uses a 20 kW laser in an 800 km Sun Synchronous Orbit to detect and track debris objects from a distance of 800 km. By emitting high-intensity laser pulses, the system can decelerate and reduce the lifetime of debris objects, effectively reducing the population of small debris objects in LEO.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Physics, Fluids & Plasmas
G. M. Petrov, A. Davidson, D. Gordon, J. Penano
Summary: A numerical model for laser-matter interactions in the warm dense matter regime is presented, incorporating collisional and transport data calculated using quantum model and classical two-temperature model. The synergy between two-temperature and average atom models has been demonstrated in solving heating and melting of Al by short-pulse laser. The research provides a more rigorous definition for solid and plasma states of the metal based on physical conditions, rather than electron temperature.
Article
Materials Science, Multidisciplinary
Jean-Luc Deziel, Louis J. Dube, Charles Varin
Summary: The study examines the controversy over the possibility of triggering ionization avalanche in dielectrics with laser-induced breakdown on a subpicosecond time scale, and the relative importance of carrier-impact ionization versus field ionization. By proposing a rate-equation model that tracks the gradual heating of charge carriers and dynamically defines collisional impact rate, the research demonstrates computational simplicity and the ability to extract effective values from experimental data. The model matches experimental scaling trends for laser-induced damage threshold of various dielectric materials for pulse durations ranging from a few femtoseconds to a few picoseconds, indicating potential advantages for large-scale, three-dimensional electromagnetic modeling of laser-induced breakdown in transparent media.
Article
Physics, Applied
Patrick Mc Kearney, Soeren Schaefer, Simon Paulus, Michael Roser, Fabian Piermaier, Ingo Lebershausen, Stefan Ralf Kontermann
Summary: Ultrashort pulse laser processing can improve the optical absorptance of sulfur hyperdoped black silicon for infrared optoelectronic applications, but it may also result in amorphous and polycrystalline phases and electrically inactive sulfur impurities. This study demonstrates an ultrafast laser heating process that recrystallizes the material, activates the sulfur dopants, and maintains sub-bandgap absorption. The process also recovers the optical activity of sulfur states deactivated by thermal annealing, making it highly applicable for material functionalization due to its localized heat input and high cooling rates.
JOURNAL OF APPLIED PHYSICS
(2023)
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
Chemistry, Physical
Niklas Osterloh, Tianluo Pan, Karina Morgenstern
Summary: Ultra-short laser illumination can be used to engineer materials by light, particularly in adjusting surface properties and nanoscale surface restructuring. In this study, we observed the formation of nanoscale clusters on a copper sample below its ablation threshold, and found that the size and shape of these clusters varied significantly across the laser spot. Our findings highlight the importance of local fluence for specific types of nanoclusters.
NANOSCALE HORIZONS
(2022)
Article
Materials Science, Multidisciplinary
Pascal Plettenberg, Bernd Bauerhenne, Martin E. Garcia
Summary: Data-driven interatomic potentials based on machine-learning approaches are widely used for large-scale simulations of materials. However, these potentials are limited when it comes to describing situations with excited electrons. In this study, a neural network potential with explicit dependence on electronic temperature is proposed. The potential accurately reproduces important physical properties and allows for simulations of laser-induced surface modifications on a thin film at ultra-large length and time scales.
COMMUNICATIONS MATERIALS
(2023)
Article
Mechanics
Susana Montoya-Reyes, Rodrigo Sanchez
Summary: This study explores the rheology of granular systems, focusing on single-particle behavior, using a computational system with capillary interparticle interactions. The results reveal the existence of Newtonian or viscoelastic behavior, with the latter resembling the Voigt model of a fluid. These findings suggest analogies with thermal systems.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2022)
Article
Chemistry, Physical
Hao Huang, Leonid Zhigilei
Summary: Short-pulse laser irradiation of a colloidal solution of nanoparticles is an effective method for fragmenting the nanoparticles and producing smaller nanoparticles and atomic clusters with desired properties. A computational model capable of realistic treatment of various processes reveals two distinct channels of formation of the fragmentation products. The nanoparticles experience ultrafast quenching in the water environment, leading to high density of twin boundaries and crystal defects that enhance catalytic applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Materials Science, Ceramics
Jie Chen, Qinglong An, Weiwei Ming, Ming Chen
Summary: The study investigated the laser-induced ablation mechanism and products of SiCf/SiC composites through numerical simulation and experiments, finding that the ablation depth could be controlled by adjusting laser parameters, with continuous-wave (CW) mode resulting in greater depth. Adjusting the scanning speed and spacing were significant factors in controlling the depth of laser-induced ablation.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Thermodynamics
Qian Huang, Shuiqing Li, Yachan Shao, Yingqi Zhao, Qiang Yao
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Thermodynamics
Jili Wei, Shuiqing Li, Yihua Ren, Yiyang Zhang, Stephen D. Tse
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Thermodynamics
Shuiqing Li, Yang Xu, Qi Gao
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Thermodynamics
Yong Tang, Qiang Yao, Wei Cui, Jiankun Zhuo, Shuiqing Li
COMBUSTION SCIENCE AND TECHNOLOGY
(2020)
Article
Engineering, Chemical
Jili Wei, Yihua Ren, Yiyang Zhang, Baolu Shi, Shuiqing Lia
JOURNAL OF AEROSOL SCIENCE
(2019)
Article
Thermodynamics
Yihua Ren, Wei Cui, Heinz Pitsch, Shuiqing Li
COMBUSTION AND FLAME
(2020)
Article
Thermodynamics
Jinguo Sun, Yihua Ren, Yong Tang, Shuiqing Li
Summary: This study investigates the extinction characteristics of premixed stagnation flames (PSFs) under different conditions and the impact of flame stability by air flow pulsations. Through experiments and numerical simulations, it is revealed that wall heat flux and air pulsations have significant effects on the extinction stretch rate and flame stability in PSFs.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Thermodynamics
Yihua Ren, Ke Ran, Stephan Kruse, Joachim Mayer, Heinz Pitsch
Summary: Core-shell carbon metal-oxide nanocomposites were synthesized in a counterflow burner with independent control of precursor loading rate and fuel mass fraction. In-situ laser diagnostics and TEM were used to investigate the formation mechanism, revealing two steps in the growth process. By adjusting precursor concentration and fuel mass fraction, the core size of metal oxides and carbonaceous layer thickness can be tailored independently.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Energy & Fuels
Yihua Ren, Jinzhi Cai, Heinz Pitsch
Summary: Flame spray pyrolysis is a promising technology for synthesizing metal-oxide nanomaterials, but numerical simulation faces challenges. A single-droplet model has been developed to describe multicomponent droplet combustion and guide precursor and process design.
Article
Chemistry, Physical
Yihua Ren, Yiyang Zhang, Qian Mao, Heinz Pitsch
JOURNAL OF PHYSICAL CHEMISTRY C
(2020)
Article
Thermodynamics
Yihua Ren, Albrecht Kreischer, Florence Cameron, Heinz Pitsch
Summary: A new spectral correction method is proposed to eliminate errors in elemental ratio measurements in laser-induced plasma. The method allows for quantitative measurement of mixture fractions in flames after correction.
COMBUSTION AND FLAME
(2022)
Article
Chemistry, Physical
Dingyu Hou, Qian Mao, Yihua Ren, Kai H. Luo
Summary: Flame aerosol synthesis is a promising method for producing carbon-metal oxide nanocomposites, but the formation and growth mechanisms of such materials are not well understood. In this study, reactive force-field molecular dynamics simulations were used to gain atomic insights into the initial stage of carbon coating on titania nanoparticles. It was found that the optimal temperature range for carbon coating is below 1200 K, and at higher temperatures, hydrocarbons tend to form larger carbonaceous species instead of coating onto the particle surface.
Article
Chemistry, Physical
Maximilian Hellmuth, Bingjie Chen, Chaimae Bariki, Liming Cai, Florence Cameron, Alina Wildenberg, Can Huang, Sebastian Faller, Yihua Ren, Joachim Beeckmann, Kai Leonhard, Karl Alexander Heufer, Nils Hansen, Heinz Pitsch
Summary: Bio-hybrid fuels, such as heterocyclic acetals 1,3-dioxane and 1,3-dioxolane, show promise for achieving a carbon-neutral and low-emission future in transportation. Comprehensive experimental and numerical investigations were conducted to understand the combustion chemistry and pollutant formation of these fuels. The results revealed differences in reactivity and pollutant formation between 1,3-dioxane and 1,3-dioxolane, despite their similar molecular structures.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Physics, Fluids & Plasmas
Wenwei Liu, Sheng Chen, Chuan-Yu Wu, Shuiqing Li