Numerical simulation methods were used in this study to examine the generation and modulation of supercontinuum (SC) spectra using Airyprime pulses in a photonic crystal fiber (PCF) with three zero-dispersion wavelengths (ZDWs). To clarify, the influence of essential initial pulse parameters (including the truncation coefficient a, initial chirp C, and peak power P) on spectral broadening and pulse evolution was systematically assessed. The results demonstrate that a smaller truncation coefficient, greater initial chirp, and elevated peak power promote enhanced supercontinuum generation. Under optimized pumping conditions, specifically a central wavelength of 1064 nm, a pulse width of 50 fs, and a peak power of 5 kW, a broadband and relatively flat supercontinuum spanning approximately 1000 nm was generated. Furthermore, comparative analysis of photonic crystal fibers with one, two, and three zero-dispersion wavelengths indicated that the three zero-dispersion wavelength fiber supports greater spectral broadening due to the involvement of tunneling soliton components. In addition, comparing Airy and Airyprime pulses revealed that Airyprime pulses induce collisions in the time domain, filling the collapse structure between blue-shifted dispersive waves (B-DWs) and higher-order solitons in the frequency domain and improving the flatness of the supercontinuum. Overall, these findings establish a theoretical basis for generating and manipulating high-power mid-infrared supercontinuum spectra.

In recent years, Pearcey-Gaussian (PG) beams have attracted much attention in optics due to their unique properties, such as self-flip, self-focusing, self-healing, and asymmetric trailing. However, studies on the evolutionary properties of this beam in nonlocal media still need to be improved, limiting the comprehensive understanding of its transport behavior. In this paper, the spatial and frequency domain evolution of the trailing-leading PG beam and the trailing-lagging PG- beam in nonlocal media are investigated in depth. The effects of the parameters of the nonlocal media (nonlinear coefficients N and characteristic width sigma) and the initial parameter of the PG beams (truncation coefficients a) on the evolution characteristics are explored. The results show that the nonlinear coefficient N, the characteristic width sigma, and the truncation coefficient a significantly affect the peak energy of the primary flap, the intensity of the sidelobe, and its deflection angle in the spatial domain of the beam. The study then compares the propagation evolution of solitons, Airy beams, and PG beams in nonlocal media, finding that the PG beam exhibits a noticeable linear deflection to the right in the spatial domain, while the spectrum's central position remains stable without significant changes. Finally, the period and peak power variations of breathers formed by PG+ beam in nonlocal media are investigated. The results provide a necessary theoretical basis for manipulating beams in nonlocal media.

The supercontinuum generation and manipulation of Airy-Gaussian pulses in a photonic crystal fiber with three zero-dispersion points are studied using the split-step Fourier method. Firstly, the spectral evolution of Airy-Gaussian pulses in four photonic crystal fibers with different barrier widths was discussed, and the optimal fiber was determined after considering the factors of width and flatness. By analyzing the mechanism of supercontinuum generation in photonic crystal fibers with single, double and three zero-dispersion points, it is found that the photonic crystal fiber with three zero-dispersion points have a larger spectral width due to the component of tunneling solitons. Then, the effects of four characteristic parameters (truncation factor a, distribution factor χ0, initial chirp C and central wavelength λ) on forming the supercontinuum spectrum of Airy-Gaussian pulses are analyzed in detail. The results show that the spectral width and energy intensity of the dispersive wave and tunneling soliton generation can be well controlled by adjusting the barrier width and initial parameters of the pulse. These research results provide a theoretical basis for generating and manipulating high-power mid-infrared supercontinuum sources.

The propagation characteristics of Airy beams in an inhomogeneous medium with periodic potential are studied theoretically and numerically. The Gross–Pitaevskii equation was solved with periodic potential using the separating variables method, and a breathing soliton solution and the breathing period were obtained. Further, the propagation properties of an Airy beam, and the interaction between two Airy beams while considering the medium parameters and beam parameters were numerically simulated in detail. First, we discuss the influence of the initial medium parameters (modulation intensity P and modulation frequency ω) on the propagation characteristics. Then, we investigate the effect of the initial beam parameters (initial chirp C and position x0) on the propagation characteristics. Lastly, the interaction of two Airy beams with opposite spatial positions for different phase φ, amplitude A, and initial interval x0 is analyzed. The breathing period and central position of the breathing solitons could be controlled by changing the initial medium parameters. By varying the initial beam parameters, the deflection direction and size, and the maximal intensity of the breathing solitons were manipulated. The breathing solitons of different bound states were formed by changing the phase φ, amplitude A, and initial interval x0 of two Airy beams. The results provide a theoretical basis for the propagation and manipulation of Airy beams.

The evolution of Cos−Gaussian beams in periodic potential optical lattices is theoretically and numerically investigated. By theoretical analysis, a breathing soliton solution of the Gross–Pitaevskii equation with periodic potential is obtained, and the period of the breathing soliton is solved. In addition, the evolution of Cos−Gaussian beams in periodic potential optical lattices is numerically simulated. It is found that breathing solitons generate by appropriately choosing initial medium and beam parameters. Firstly, the effects of the initial parameters of Cos−Gaussian beams (initial phase and width) on its initial waveform and the propagation characteristics of breathing soliton are discussed in detail. Then, the influence of the initial parameters (modulation intensity and modulation frequency) of a photonic lattice on the propagation characteristics of breathing solitons is investigated. Finally, the effects of modulation intensity and modulation frequency on the width and period of the breathing soliton are analyzed. The results show that the number of breathing solitons is manipulated by controlling the initial parameters of Cos−Gaussian beams. The period and width of a breathing soliton are controlled by manipulating the initial parameters of a periodic photonic lattice. The results provide some theoretical basis for the generation and manipulation of breathing solitons.

结合分步傅里叶方法和四阶Runge-Kutta积分法，研究了有限能量cosh-Airy脉冲在双零色散介质中的超连续谱产生与操控。首先，详细讨论了特征参数截断系数a、初始啁啾C和分布因子χ 0 对cosh-Airy脉冲在双零色散介质中的演化影响，并统计了a、C和χ 0 对超连续谱宽度的影响。然后，进一步研究了高阶非线性效应对cosh-Airy脉冲产生超连续谱的影响。结果表明：通过操控coshAiry脉冲的特征参数可以控制超连续谱的宽度；当存在高阶非线性效应时，超连续谱的平坦性会受到影响。研究结果为超连续谱的产生和操控以及宽带激光光源提供一些理论基础。

The evolution characteristics of an Airy beam in PT symmetric medium by using split-step Fourier method was investigated. Then the impact of truncation width, modulation depth, and modulation width on the propagation properties of soliton generated from an Airy beam was discussed in detail. The results illustrate that when an Airy beam propagates in a PT symmetric medium, a soliton with periodic variation is shedded at the main peak position and a lateral offset is generated. Moreover, it is demonstrated that with decreasing truncation width a, increasing modulation depth P and modulation factor w, the peak-to-average power ratio of a soliton from Airy beam increases, which causes the beam interference and beam distortion become more and more. With decrement of modulation depth P and increment of modulation factor w, the peak intensity and peak-to-average power ratio of a soliton from an Airy beam jump obviously, leading to decreasing propagation stability of a soliton. However, the shedding soliton can still propagates stably in a long distance.

Water electrolysis via hydrogen evolution reaction (HER) is a promising approach in the production of hydrogen. In spite of its unique physical and chemical properties, there are few reports about black arsenic (b-As) as a catalyst for HER. Our first-principles calculations show that doping could play an important role in affecting the catalytic properties of b-As. Among different dopants studied, the O atom is most likely to be embedded into the b-As lattice. The embedded OAs atoms or clusters could tune the Fermi level, increase the binding strength of hydrogen to an appropriate level and thus significantly improving catalytic performance for HER.

A novel Ag3PO4/CeO2 composite was fabricated by in situ wrapping CeO2 nanoparticles with Ag3PO4 through a facile precipitation method. The photocatalytic properties of Ag3PO4/CeO2 were evaluated by the photocatalytic degradation of MB and phenol under visible light and UV light irradiation. The photocatalytic activity of the composite is much higher than that of pure Ag3PO4 or CeO2. The rate constant of MB degradation over Ag3PO4/CeO2 is more than 2 times and 20 times than those of pure Ag3PO4 and CeO2 under visible light irradiation, respectively. The Ag3PO4/CeO2 composite photocatalyst also shows higher photocatalytic activity for the colorless phenol degradation compared to pure Ag3PO4. Moreover, the Ag3PO4/CeO2 sample has almost no loss of photocatalytic activity after five recycles under the irradiation of visible light and UV light, indicating that the composite has good photocatalytic stability. The excellent photocatalytic activity of the Ag3PO4/CeO2 composite is closely related to the fast transfer and efficient separation of electron-hole pairs at the interfaces of the two semiconductors derived from the matching band positions between CeO2 and Ag3PO4. This newly constructed Ag3PO4/CeO2 composite, with promising and fascinating visible light-driven photocatalytic activity as well as good stability, could find potential applications in environmental purification and solar energy conversion.

Electroless Ni–Fe–P alloys were deposited onto copper substrate from a bath using tri-ammonium citrate and/or tri-sodium citrate as complexing agents. The effects of complexing agents on the corrosion resistance of the alloys were investigated. The variation of the complexing agent leads to the change of corrosion resistance of the alloys due to the composition and the structure change, the alloys obtained with tri-ammonium citrate as complexing agents show better corrosion resistance than those with tri-sodium citrate as complexing agents. The alloys have better corrosion resistance in alkaline solution than in acid solution due to the increasing of polarization resistance.