Based on the multiple scattering method,this paper investigates a benchmark problem of the propagation of liquid surface waves over finite graphene (or honeycomb) structured arrays of cylinders.Comparing the graphene ...Based on the multiple scattering method,this paper investigates a benchmark problem of the propagation of liquid surface waves over finite graphene (or honeycomb) structured arrays of cylinders.Comparing the graphene structured array with the square structured and with triangle structured arrays,it finds that the finite graphene structure can produce more complete band gaps than the other finite structures,and the finite graphene structure has less localized ability than the other finite structures.展开更多
The angle compensation method is adopted to detect sloshing waves by laser diffraction, in the case that the wavelength of the sloshing waves is much greater than that of the incident light. The clear diffraction patt...The angle compensation method is adopted to detect sloshing waves by laser diffraction, in the case that the wavelength of the sloshing waves is much greater than that of the incident light. The clear diffraction pattern is observed to be of asymmetry, involving orders, position and interval of the diffraction spots that are discovered during the light grazing incidence. It is found that the larger the angle of incidence is, the more obvious the asymmetry is. The higher the negative diffraction orders are, the smaller the intervals between spots are. On the contrary~ in the positive region, the higher the diffraction orders are, the larger the spot intervals are. The positive interval is larger than that of the same negative diffraction order. If the incident angle reaches 1.558 rad in the experiment, all positive diffraction orders completely vanish. Based on the mechanism of phase modulation and with the Fourier transform method, the relations between the incident angle and position, interval spaces, and orders of diffraction spots are derived theoretically. The theoretical calculations are compared with the experimental data, and the comparison shows that the theoretical calculations are in good agreement with the experimental measurement.展开更多
Diffraction,inherently linked to angular spectrum and affected by spatiotemporal coupling effects,imposes a fundamental limit on wave packets propagation.This limitation is particularly acute for spatiotemporal vortex...Diffraction,inherently linked to angular spectrum and affected by spatiotemporal coupling effects,imposes a fundamental limit on wave packets propagation.This limitation is particularly acute for spatiotemporal vortex beams,where diffraction distorts the beam profile and splits topological charges.While spatiotemporal coupling engineering has enabled diffraction-free(or propagation-invariant)wave packet propagation,achieving stable vortex propagation remains a significant challenge due to inherent constraints of regular wave dispersion.Here,we overcome this challenge by tailoring the wave system’s dispersion to achieve both propagation-invariant behavior and stable vortex structures.We present the first experimental demonstration of propagation-invariant spatiotemporal vortex beams that maintain their spatiotemporal profiles and topological charges over extended propagation distances.The ability of these wave packets to stably carry diverse topological charges without splitting or deformation provides critical insights into spatiotemporal vortex dynamics and unlocks new possibilities for applications across optics,acoustics,and beyond.展开更多
基金supported by the National Natural Science Foundation of China (10932010 and 11072220)the Young Foundation of Zhejiang Normal University (KJ20100001)
文摘Based on the multiple scattering method,this paper investigates a benchmark problem of the propagation of liquid surface waves over finite graphene (or honeycomb) structured arrays of cylinders.Comparing the graphene structured array with the square structured and with triangle structured arrays,it finds that the finite graphene structure can produce more complete band gaps than the other finite structures,and the finite graphene structure has less localized ability than the other finite structures.
基金Supported by the Open Research Fund of State Key Laboratory of Transient Optics and Photonics of Chinese Academy of Sciences under Grant No SKLST201508the China Postdoctoral Science Foundation Funded Project under Grant No 2015M580945the Government of Chaoyang District Postdoctoral Research Foundation
文摘The angle compensation method is adopted to detect sloshing waves by laser diffraction, in the case that the wavelength of the sloshing waves is much greater than that of the incident light. The clear diffraction pattern is observed to be of asymmetry, involving orders, position and interval of the diffraction spots that are discovered during the light grazing incidence. It is found that the larger the angle of incidence is, the more obvious the asymmetry is. The higher the negative diffraction orders are, the smaller the intervals between spots are. On the contrary~ in the positive region, the higher the diffraction orders are, the larger the spot intervals are. The positive interval is larger than that of the same negative diffraction order. If the incident angle reaches 1.558 rad in the experiment, all positive diffraction orders completely vanish. Based on the mechanism of phase modulation and with the Fourier transform method, the relations between the incident angle and position, interval spaces, and orders of diffraction spots are derived theoretically. The theoretical calculations are compared with the experimental data, and the comparison shows that the theoretical calculations are in good agreement with the experimental measurement.
基金supported by the National Key Research and Development Program of China(2023YFA1406900 and 2022YFA1404800)the National Natural Science Foundation of China(12234007,12321161645,12221004,T2394480,and T2394481)+1 种基金Science and Technology Commission of Shanghai Municipality(22142200400,21DZ1101500,2019SHZDZX01,and 23DZ2260100)China Postdoctoral Science Foundation(2022M720810 and 2022TQ0078).
文摘Diffraction,inherently linked to angular spectrum and affected by spatiotemporal coupling effects,imposes a fundamental limit on wave packets propagation.This limitation is particularly acute for spatiotemporal vortex beams,where diffraction distorts the beam profile and splits topological charges.While spatiotemporal coupling engineering has enabled diffraction-free(or propagation-invariant)wave packet propagation,achieving stable vortex propagation remains a significant challenge due to inherent constraints of regular wave dispersion.Here,we overcome this challenge by tailoring the wave system’s dispersion to achieve both propagation-invariant behavior and stable vortex structures.We present the first experimental demonstration of propagation-invariant spatiotemporal vortex beams that maintain their spatiotemporal profiles and topological charges over extended propagation distances.The ability of these wave packets to stably carry diverse topological charges without splitting or deformation provides critical insights into spatiotemporal vortex dynamics and unlocks new possibilities for applications across optics,acoustics,and beyond.
