Article
Engineering, Multidisciplinary
Mehtab Singh, Ahmad Atieh, Amit Grover, Omar Barukab
Summary: This paper explores the enhancement of data carrying capacity in free space optics transmission systems by utilizing orbital angular momentum multiplexing technique. It demonstrates a net data capacity of 40 Gb/s over a free space transmission medium using four distinct OAM beams and compares the performance of different encoding schemes.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Wenhui Xu, Hui Li, Shouxin Duan, Hang Xu, Chenglong Zheng, Jie Li, Chunyu Song, Yating Zhang, Yun Shen, Jianquan Yao
Summary: This research presents a general design strategy for spin-multiplexing all-silicon metasurfaces in THz polarization detection. Vector beams are generated using basic building blocks with a high aspect ratio, and the incident polarization state is reconstructed using vortex beams. Additionally, a visualized parametric model is established using the illumination method of dynamically varying polarization.
Article
Multidisciplinary Sciences
Alon Luski, Yair Segev, Rea David, Ora Bitton, Hila Nadler, A. Ronny Barnea, Alexey Gorlach, Ori Cheshnovsky, Ido Kaminer, Edvardas Narevicius
Summary: This study demonstrates the generation of vortex beams of atoms and molecules by diffracting supersonic beams of helium atoms and dimers off transmission gratings. The method is general and could be applied to most atomic and molecular gases, providing new insights and possibilities in atomic physics.
Article
Chemistry, Multidisciplinary
Dale Green, Kayn A. Forbes
Summary: In this study, we systematically investigate the optical chirality density of Laguerre-Gaussian and Bessel laser beams tightly focused into nanoscale volumes. We specifically emphasize the unique contributions to optical chirality from longitudinal electromagnetic fields, which is light polarized in the direction of propagation. We study the influence of polarization, spin and orbital angular momentum, radial index, degree of focusing, and diffraction on optical chirality. The results demonstrate that the optical chirality of structured light beams at the nanoscale is significantly richer than that of the well-known circularly polarized propagating plane wave. This work lays the foundation for chiral nanophotonics and chiral quantum optics based on structured light illumination.
Article
Optics
Xue Zhang, Lingling Huang, Ruizhe Zhao, Qunshuo Wei, Xin Li, Guangzhou Geng, Junjie Li, Xiaowei Li, Yongtian Wang, Shuang Zhang
Summary: Optical vortex beams offer a new way to carry optical information with an unbounded number of orbital angular momentum channels. By tailoring the local phase gradient, multiplexed generalized vortex beams with custom-defined closed-loop beam profiles can be generated. Different polarization channels of metasurfaces are utilized to create multiple generalized vortex beams with independent intensity profiles, enabling various optical modulating capabilities such as precise particle manipulation, optical source, and OAM encryption.
LASER & PHOTONICS REVIEWS
(2022)
Article
Physics, Applied
Qi Jia, Rui Feng, Bojian Shi, Fangkui Sun, Yanxia Zhang, Hang Li, Xiaoxin Li, Yongyin Cao, Jian Wang, Weiqiang Ding
Summary: This study proposes a deep neural network (DNN)-N-2 method for compensating distorted OAM beams by extracting common features and filtering random distortions. Good agreement between experimental and simulated results is achieved.
APPLIED PHYSICS LETTERS
(2022)
Article
Optics
S. Ramakrishna, J. Hofbrucker, S. Fritzsche
Summary: In this study, we analyze the photoexcitation of atoms with a single valence electron by cylindrically polarized Laguerre-Gaussian beams. We show the variation of electric-quadrupole field sub-components in the beam cross section with beam waist and radial distance from the beam axis. The calculations reveal that the excitation rate is sensitive to both the beam waist and the distance between the target center and the beam axis. However, the excitation by a cylindrically polarized Laguerre-Gaussian beam is found to be more efficient in driving electric-quadrupole transition in the atomic target compared to circularly polarized beams.
Article
Physics, Multidisciplinary
David R. Blackman, Yin Shi, Sallee R. Klein, Mihail Cernaianu, Domenico Doria, Petru Ghenuche, Alexey Arefiev
Summary: This study investigates an alternative electron injection method using a low-density foam target and a helical laser pulse. Three-dimensional simulations demonstrate that this method can generate a high-energy, short acceleration distance, and low-divergence electron beam.
COMMUNICATIONS PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Mehtab Singh, Ahmad Atieh, Dhiman Kakati
Summary: In response to increasing information exchange needs, optical communication links are witnessing a growing demand for higher transmission rates, channel bandwidth, and spectral-efficiency. This paper reports a high-speed spectral-efficient FSO link based on OAM multiplexing technology. The link demonstrates good performance under varying weather conditions.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Optics
Xiaojin Yin, Pengqi Hao, Yupei Zhang, Ziyue Zhao, Jinze Wu, Jinhong Li
Summary: The characteristics of two noninteger cylindrical vector vortex beams (NCVVBs) propagating through a radial gradient-index (GRIN) fiber are analyzed based on the generalized Huygens-Fresnel principle. The NCVVBs exhibit periodic and stable transmission characteristics in the radial GRIN fiber. Polarization changes, the presence of spin angular momentum (SAM), and changes in the orbital angular momentum (OAM) of the NCVVBs are observed at the focal plane of the radial GRIN fiber. Spin-orbit interactions of NCVVBs are verified in the radial GRIN fiber for the first time, to the best of our knowledge.
Article
Optics
Sergey Nechayev, Joerg S. Eismann, Rasoul Alaee, Ebrahim Karimi, Robert W. Boyd, Peter Banzer
Summary: Geometrical chirality describes the violation of three-dimensional mirror symmetry in objects with a nonvanishing spatial extent, while optical chirality only focuses on the local handedness of electromagnetic fields. This study introduces the physical significance of Kelvin's chirality in the spatial structure of optical beams and demonstrates its coupling to optical chirality in experiments involving structured light beams. The research highlights the importance of Kelvin's chirality in light-matter interactions with spatially inhomogeneous phase and polarization distributions.
Article
Optics
P. de la Rosa, J. Pereiro-Garcia, M. Cano-Garcia, J. M. Oton, X. Quintana, M. A. Geday
Summary: This study presents the manufacturing and characterization of a large-size 72-electrode liquid crystal-based reconfigurable spiral phase plate. The device, driven by a custom-made driver with 72 independent channels, is capable of generating optical vortex beams with any arbitrary topological charge. The device, fabricated using direct laser writing, exhibits high fill factor and flexibility in size, surpassing previous transparent reconfigurable SPPs. Simulation results show excellent correspondence between the device and the light path.
Article
Chemistry, Multidisciplinary
Da-Jie Yang, Ji-Cai Liu
Summary: In this study, efficient and selective high-order resonances were demonstrated in symmetric and asymmetric plasmonic nanoparticles using vortex beams. A pure high-order resonance was observed in symmetric nanoparticles configured with a complete nanoring lying on the focal center. Asymmetric nanoparticles configured with a complete ring off the beam center or a splitting nanoring showed multiple resonances influenced by the ring's geometry, position, orientation, and photon OAM. These findings contribute to the understanding and control of OAM-involved light-material interactions in asymmetric nanosystems.
Article
Optics
Fajing Li, Shouping Nie, Jun Ma, Caojin Yuan
Summary: This paper proposes a modulation chiro-optical OAM (MC-OAM) holography method, which integrates OAM multiplexing technology with chiro phase modulation to improve information security capacity. The orthogonality of the axicon parameter, chiro coefficient, and rotation angle in modulating chiro phase distributions are analyzed, demonstrating their potential as additional degrees of freedom. Combined with the topological charge, these parameters serve as four optical keys, providing a four-dimensional spatial multiplexing method for information security.
Article
Physics, Applied
Yan Wang, Xuan Wang, Chenglong Jia
Summary: Recent advances in twisted electron beams allow for exploration of the role of orbital angular momentum on electromagnetic microstructures, with high resolution representation provided by phase shifting detection.
APPLIED PHYSICS LETTERS
(2023)
Article
Engineering, Multidisciplinary
Zia Ullah, Hasan Saeed Qazi, Ahmad Alferidi, Mohammed Alsolami, Badr Lami, Hany M. Hasanien
Summary: This study presents a novel method for optimizing energy trading within microgrids by using a hybrid of particle swarm optimization and gravitational search algorithms. The proposed approach promotes cooperative energy trading among microgrids and the main grid, considering network constraints and the uncertainty of renewable energy. Simulation results show that this method maximizes renewable energy utilization, reduces load burden on the main grid, and significantly decreases energy costs.
ALEXANDRIA ENGINEERING JOURNAL
(2024)
Article
Engineering, Multidisciplinary
Chin Joo Tan
Summary: In this study, the effect of mesh sensitivity on the hole-flanging process was investigated by varying the mesh layouts and punch surface meshing techniques. The results showed that the punch displacement and mesh parameters have significant effects on the wall thickness distributions and forming load profiles. Additionally, calibrating the simulation model's stiffness with the experimental peak load through matching the simulated peak load with the experimental peak under stability conditions was recommended.
ALEXANDRIA ENGINEERING JOURNAL
(2024)
Article
Engineering, Multidisciplinary
Wei-Chao Yang, Lun Zhao, E. Deng, Yi-Qing Ni, Wen Zhao, Yi-Kang Liu, De-Hui Ouyang
Summary: This paper establishes a three-dimensional coupled train-subgrade-wind dynamics model, and investigates the aerodynamic load variation and flow field mechanisms when high-speed trains transit different types of subgrade-cutting transition sections in crosswind conditions. The results indicate that the aerodynamic performance of the train deteriorates in these transition sections, and the aerodynamic load of the head car varies in different operating scenarios.
ALEXANDRIA ENGINEERING JOURNAL
(2024)
Article
Engineering, Multidisciplinary
Shashi Bhushan, Anoop Kumar, Eslam Hussam, Manahil SidAhmed Mustafa, Mohammed Zakarya, Wedad R. Alharbi
Summary: In the sample survey theory, accurate estimation of parameters is essential for survey practitioners. This paper suggests optimal classes of estimators by modifying conventional estimators under stratified ranked set sampling (SRSS). The suggested estimators have been shown to outperform traditional estimators, particularly regression (BLU) estimators, both theoretically and experimentally.
ALEXANDRIA ENGINEERING JOURNAL
(2024)
Article
Engineering, Multidisciplinary
Laila A. Al-Essa, Ahmed A. Soliman, Gamal A. Abd-Elmougod, Huda M. Alshanbari
Summary: In this study, the class of lifetime distributions with bathtub-shaped failure rate functions is examined. Statistical inference methods are used to estimate the parameters of the model, and the Bayesian approach is compared with classical methods. The study also discusses the evaluation of product relative merits based on lifetime duration under a hybrid censoring scheme.
ALEXANDRIA ENGINEERING JOURNAL
(2024)
Article
Engineering, Multidisciplinary
Mohammad Partohaghighi, Marzieh Mortezaee, Ali Akguel, Ahmed M. Hassan, Necibullah Sakar
Summary: The study introduces a new variant of the fractal-fractional diffusion equation using the fractal-fractional operator. It proposes a novel operational matrix technique to solve the equation, transforming it into an algebraic system. The study presents graphical and tabular representations of exact and approximated solutions, along with corresponding errors, and conducts comparative analysis of solutions at specific time points.
ALEXANDRIA ENGINEERING JOURNAL
(2024)