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Corrosion and Fatigue Testing of Microsized 304 Stainless Steel Beams Fabricated by Femtosecond Laser

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Journal of Materials Science & Technology 2009年第2期25卷 187-193页

作者： Qiang Zhang Xingpeng Guo Nengli Dai peixiang lu Department of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 China Wuhan National Laboratory for Optoelectronics and School of Optoelectronics Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

The 304 stainless steel （SS） microcantilever specimens with dimensions of 30 #m ×30 #m ×50 #m （thicknessx width × length） were fabricated by femtosecond （fs） laser. The microsized cantilevers of good quality with structure and dimensions according commendably with that of the designed cantilever were obtained. The result shows that fs laser micromachining is a promising method for directly fabricating metallic microcomponents. Corrosion and fatigue properties of microsized specimens were carried out on the microsized 304 SS cantilever beams by a newly developed fatigue testing machine. The results show that the microsized 304 SS specimens appear to have an improved resistance towards localized corrosion compared to ordinary-sized 304 SS specimens after the static corrosion testing. The testing result shows that the presence of corrosive solution reduces the fatigue lifetime of the 304 SS specimen by a factor of 10-100. The maximum bending loads measured by fatigue testing machine decrease rapidly at the terminal stage of environment assisted fatigue testing. Corrosion fracture first occurred at the range of notch with a higher tensile bending stress, and exhibited clear evidence of trans-columnar fracture detected by SEM （scanning electron microscopy）.

关键词： Corrosion fatigue Stainless steel Femtosecond laser Microsystem

Phase-dependence correlated electron momentum distribution from nonsequential double ionization of N2 by few-cycle laser pulses

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Frontiers of Optoelectronics 2010年第2期3卷 184-189页

作者： Yueming ZHOU peixiang lu Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

Using the classical three-dimensional（3D）ensembles, we have investigated nonsequential double ionization（NSDI） of N2by phase-stabilized few-cycle pulses. We find that the correlated electron momentum distributions in the direction parallel to the laser field strongly depend on the carrier-envelope phase（CEP） of few-cycle pulses, and this phase dependence is not affected by the alignment of the molecular axis relative to the laser field. Back analysis reveals that the ionization rate of the first electron and the recollision energy play a main role in the electron momentum distributions. Our results suggest that the few-cycle pulses with stabilized phase can serve as a powerful tool to investigate the recollision dynamics in NSDI of molecules.

关键词： 36\f2\d3\1c\hcm0000124800.html

Taking snapshots of a moving electron wave packet in molecules using photoelectron holography in strong-field tunneling ionization

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Chinese Physics B 2021年第12期30卷 348-353页

作者： Mingrui He Yang Fan Yueming Zhou peixiang lu Department of Basic Courses Naval University of EngineeringWuhan 430033China School of Physics and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

Coherent superposition of electronic states induces attosecond electron motion in *** theoretically investigate the strong-field ionization of this superposition state by numerically solving the time-dependent Schrodinger *** the obtained photoelectron momentum distribution,an intriguing bifurcation structure appears in the strong-field holographic interference *** demonstrate that this bifurcation structure directly provides complete information about the status of the transient wave function of the superposition state:the horizontal location of the bifurcation in the momentum distribution reveals the relative phase of the involved components of the superposition state and the vertical position indicates the relative ***,this bifurcation structure takes a snapshot of the transient electron wave packet of the superposition state and provides an intuitive way to monitor electron motion in molecules.

关键词： strong-field ionization photoelectron holography charge migration

Progress of photonic crystal fibers and their applications

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Frontiers of Optoelectronics 2009年第1期2卷 50-57页

作者： Wei CHEN Jinyan LI peixiang lu Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology State Key Laboratory of Optical Communication Technologies and Networks Optical Fiber Department of Fiberhome Telecommunication Technologies Co. Ltd.

In this article, the fabrication technologies of photonic crystal fibers(PCFs) and their applications at home and abroad were formulated at length, especially in fields such as large mode-area active PCFs, fiber lasers,birefringence fibers, sensors, high nonlinear PCFs, frequency transformation, dispersion compensation PCFs,wideband communication for optical network systems, and photonic band-gap fibers. Finally, according to the above analysis, the prospects and developing trends of PCFs were presented.

关键词： 14\82\7f\3e\hcm0000078507.html

Extracting the phase distribution of the electron wave packet ionized by an elliptically polarized laser pulse

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Frontiers of physics 2021年第3期16卷 185-192页

作者： Ya-Nan Qin Min Li Yudi Feng Siqiang luo Yueming Zhou peixiang lu Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and TechnologyWuhan430074China Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of TechnologyWuhan430205China

We use an interferometic scheme to extract the phase distribution of the electron wave packet from above-threshold ionization in elliptically polarized laser *** this scheme,an electron wave packet released from a circularly polarized laser pulse acts as a reference wave and interferes with the electron wave packet ionized by a time-delayed counter-rotating elliptically polarized laser *** generated vortex-shaped interference pattern in the photoelectron momentum distribution enables us to extract the phase distribution of the electron wave packet in the elliptically polarized laser pulse with high *** artificially screening the ionic potential at different ranges when solving the time-dependent Schördinger equation,we find that the angle-dependent phase distribution of the electron wave packet in the elliptically polarized laser field shows an obvious angular shift as compared to the strong-field approximation,whose value is the same as the attoclock *** also show that the amplitude of the angle-dependent phase distribution is sensitive to the ellipticity of the laser pulse,providing an alternative way to precisely calibrate the laser ellipticity in the attoclock measurement.

关键词： above-threshold ionization photoelectron interference vortex structure

A study on soft x-ray spectra from pulsed 1 μm Nd:YAG laser-induced ytterbium plasmas

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Plasma Science and Technology 2020年第10期22卷 119-125页

作者： Tao WU Jun HE Li YANG peixiang lu Hubei Key Laboratory Optical Information and Pattern Recognition School of Optical Information and Energy EngineeringWuhan Institute of TechnologyWuhan 430205People's Republic of China Guangdong Intelligent Robotics Institute Dongguan 523808People's Republic of China

The Nd:YAG laser with a wavelength of 1.064 μm was used to generate plasmas on a high-purity solid ytterbium(70 Yb) target in a vacuum chamber. The soft x-ray time-and space-integration spectra from the Yb plasmas were measured in the wavelength range of 1.0–8.5 nm under different power densities. The atomic spectral data of the unresolved transition arrays from highly charged Yb ions were calculated based on Cowan's suite of codes, including configuration interaction. The calculated Gaussian envelope of the emission determined by the weighted spontaneous transition rates was compared with the experimental spectra, and a good agreement between them was obtained. The spatial-temporal evolutions of the plasmas under the experimental conditions are simulated based on the collisional-radiative model, enabling the understanding of the mechanism of the plasma conditions for optimal water window waveband emission output.

关键词： laser produced plasma water window sources unresolved transition arrays ytterbium

Dispersion-flattened Bragg photonic crystal fiber for large capacity optical communication system

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Frontiers of Optoelectronics 2009年第3期2卷 289-292页

作者： Wei CHEN Shiyu LI peixiang lu Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology State Key Laboratory of Optical Communication Technologies and Networks Fiberhome Telecommunication Technologies Co.Ltd.

A novelty dispersion ultra-flattened Bragg photonic crystal fiber(PCF) has been fabricated in this paper. The fiber is composed of compound cores and periodical claddings with 11 coaxial rings. It has flattened dispersion of 8.5±1.3 ps·(nm·km)–1in the communication wavelength range of 1460–1625 nm. Its dispersion slope alters from – 0.0428 to 0.0392 ps·nm–2·km–1. The low attenuation of 0.52 d B/km and low bending loss of 0.09 d B at 1550 nm of the fiber are also achieved. The Bragg PCF has enormously potential application in the fields of dense wavelength division multiplexing systems because of its superior dispersion properties and easy splicing performances.

关键词： communication fabrication low dispersion optoelectronic devices photonic crystal fiber (PCF)

All-optical attosecond time domain interferometry

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National Science Review 2021年第10期8卷 15-22页

作者： Zhen Yang Wei Cao Yunlong Mo Huiyao Xu Kang Mi Pengfei Lan Qingbin Zhang peixiang lu Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and Technology Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of Technology CAS Center for Excellence in Ultra-intense Laser Science

Interferometry, a key technique in modern precision measurements, has been used for length measurement in engineering metrology and astronomy. An analogous time-domain interferometric technique would represent a significant complement to spatial domain applications and require the manipulation of interference on extreme time and energy scales. Here, we report an all-optical interferometer using laser-driven high order harmonics as attosecond temporal slits. By controlling the phase of the temporal slits with an external field, a time domain interferometer that preserves both attosecond temporal resolution and hundreds of me V energy resolution is implemented. We apply this exceptional temporal resolution to reconstruct the waveform of an arbitrarily polarized optical pulse, and utilize the provided energy resolution to interrogate the abnormal character of the transition dipole near the Cooper minimum in argon. This novel attosecond interferometry paves the way for high precision measurements in the time-energy domain using all-optical approaches.

关键词： interferometry attosecond all-optical precision measurement

Attosecond spectroscopy for filming the ultrafast movies of atoms,molecules and solids

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Chinese Physics B 2022年第12期31卷 191-211页

作者： Lixin He Xiaosong Zhu Wei Cao Pengfei Lan peixiang lu Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and TechnologyWuhan 430074China Optical Valley Laboratory Hubei 430074China

Three decades ago,a highly nonlinear nonpertubative phenomenon,now well-known as the high harmonic generation(HHG),was discovered when intense laser irradiates gaseous *** the HHG produces broadband coherent radiation,it becomes the most promising source to obtain attosecond *** door to the attosecond science was opened ever *** this review,we will revisit the incredible adventure to the ***,the progress of attosecond pulse generation is ***,we introduce the efforts on imaging the structures or filming the ultrafast dynamics of nuclei and electrons with unprecedented attosecond temporal and Angstrom spatial resolutions,utilizing the obtained attosecond pulses as well as the high harmonic spectrum itself.

关键词： strong-field physics attosecond science high harmonic generation ultrafast spectroscopy