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The optical radiation force (ORF) and optical spin torque (OST) on an absorptive electromagnetic conductor (AEMC) sphere by an arbitrary-shaped optical polarized beam are investigated in the framework of the generalized Lorenz–Mie theory (GLMT). The analytical expressions of ORF and OST are derived, and both of them are decomposed into three components (co-polarized, cross-polarized, and interference components) due to the unique "optical rotation" effect of the AEMC. The ORF and OST exerted on both a PEMC and an AEMC sphere by an Airy beam are discussed, and the impact of the losses M i of AEMC is focused on. Besides, the influence of particle size parameter k a and admittance parameter M on the ORF and OST are also mainly analyzed. The optical pulling force built on this system is paid attention to and discussed. And the impact of the polarization states of the incident beam on the ORF and OST is also discussed. Furthermore, the comparison of ORF that the Airy beam interacts with a dielectric sphere and an AEMC sphere is studied emphatically. The findings in this manuscript will take effect on particle manipulation, optical spanners, optical tweezers, and metamaterial field. • The optical radiation force and torque exerted on an absorptive electromagnetic conductor (AEMC) sphere by an arbitrary-shaped optic. • The co-polarized, cross-polarized, and interference components of the optical radiation force and torque are studied. • Both the longitudinal and the transversal optical radiation force (including the optical pulling force) and torque are analyzed. • The comparison of ORF that the Airy beam interacts with a dielectric sphere and an AEMC sphere is studied. • The effects from the beam parameters of Airy beam and particle parameters are analyzed. [ABSTRACT FROM AUTHOR]

• The generalized Lorenz-Mie theory (GLMT) for a laser beam of arbitrary shape illuminating a perfect electromagnetic conductor (PEMC) sphere is presented. • The precise expressions of the total electric field intensity, the scattering efficiency, and its components are attained by the GLMT. • The effects of dimensionless size and admittance parameter on the total electric field intensity and the scattering efficiency are calculated and analyzed. • The effects of wave parameters on the scattering efficiency are calculated and discussed. The generalized Lorenz-Mie theory (GLMT) for a laser beam of arbitrary shape illuminating a perfect electromagnetic conductor (PEMC) sphere is presented. Making use of the vector angular spectrum decomposition method (VASDM), and the multipole expansion method (MEM), in which any beam is expressed in terms of vector spherical wave functions (VSWFs) and beam shape coefficients (BSCs), the BSCs are obtained and expressed by a vector angular spectrum. The incident and scattering waves are expanded using VSWFs. A relation between the coefficients of the scattering fields and the BSCs of the incident beam is established considering the appropriate boundary conditions at the surface of the PEMC sphere. Expressions for the extinction, scattering, and absorption cross-sections are derived and computed. By isolating the co-polarization and cross-polarization components of the scattering coefficients, individual expressions of these physical quantities are also provided. Considering the vector Bessel and Airy polarized beams as examples, the total electric field intensity, scattering cross-section and its co-polarized and cross-polarized components are numerically computed and discussed. The effects of beam polarization, size parameter of the sphere, the admittance M , and beam parameters are analyzed. It has been found that the intensity and distribution of the total (incident + scattered) electric field intensity in the transverse (y z) plane depends on the incident beam characteristics and its polarization states. As the dimensionless size k a increases, the amplitude of the scattering cross-section increases and then decreases as k a increases. As the admittance parameter M changes, there are different characteristics if the incident beam is different. Nonetheless, there is a common behavior that the trend of the co-polarized component of the scattering cross-section decreases first and then increases regardless of the beam and its polarization state. When it comes to the trend of the cross-polarized component versus M , it is opposite to that of the co-polarized component. A few resonance peaks are manifested in the plots when the incident beam is radially or azimuthally polarized. The results may have promising applications in scattering, particle manipulation, optical trapping, and other related researches dealing with a sphere exhibiting rotary polarization. [ABSTRACT FROM AUTHOR]

• The generalized Lorenz-Mie theory (GLMT) for a laser beam of arbitrary shape illuminating a perfect electromagnetic conductor (PEMC) sphere is presented. • The precise expressions of the total electric field intensity, the scattering efficiency, and its components are attained by the GLMT. • The effects of dimensionless size and admittance parameter on the total electric field intensity and the scattering efficiency are calculated and analyzed. • The effects of wave parameters on the scattering efficiency are calculated and discussed. The generalized Lorenz-Mie theory (GLMT) for a laser beam of arbitrary shape illuminating a perfect electromagnetic conductor (PEMC) sphere is presented. Making use of the vector angular spectrum decomposition method (VASDM), and the multipole expansion method (MEM), in which any beam is expressed in terms of vector spherical wave functions (VSWFs) and beam shape coefficients (BSCs), the BSCs are obtained and expressed by a vector angular spectrum. The incident and scattering waves are expanded using VSWFs. A relation between the coefficients of the scattering fields and the BSCs of the incident beam is established considering the appropriate boundary conditions at the surface of the PEMC sphere. Expressions for the extinction, scattering, and absorption cross-sections are derived and computed. By isolating the co-polarization and cross-polarization components of the scattering coefficients, individual expressions of these physical quantities are also provided. Considering the vector Bessel and Airy polarized beams as examples, the total electric field intensity, scattering cross-section and its co-polarized and cross-polarized components are numerically computed and discussed. The effects of beam polarization, size parameter of the sphere, the admittance M , and beam parameters are analyzed. It has been found that the intensity and distribution of the total (incident + scattered) electric field intensity in the transverse (y z) plane depends on the incident beam characteristics and its polarization states. As the dimensionless size k a increases, the amplitude of the scattering cross-section increases and then decreases as k a increases. As the admittance parameter M changes, there are different characteristics if the incident beam is different. Nonetheless, there is a common behavior that the trend of the co-polarized component of the scattering cross-section decreases first and then increases regardless of the beam and its polarization state. When it comes to the trend of the cross-polarized component versus M , it is opposite to that of the co-polarized component. A few resonance peaks are manifested in the plots when the incident beam is radially or azimuthally polarized. The results may have promising applications in scattering, particle manipulation, optical trapping, and other related researches dealing with a sphere exhibiting rotary polarization. [ABSTRACT FROM AUTHOR]

Abstract: The scattering of an axicon-generated Bessel beam (AGBB) by a sphere is investigated. An analytical formula for the calculation of Beam Shape Coefficients (BSCs) of an AGBB is first derived according to the Integral Localized Approximation (ILA). After the verification of BSCs by the comparison of the reconstructed field using BSCs with the original field obtained from the definition, the far-field scattered intensity is evaluated, and the rainbow produced by AGBB is also studied. The effect of angle on the far-field scattered intensity and the first rainbow is analyzed in detail. Such investigation could provide a useful tool for the research on radiation forces and torques, which is important in optical tweezers and the related optical manipulation applications. [Copyright &y& Elsevier]

• The scattering of a non-paraxial Bessel pincer light-sheet by a dielectric sphere of arbitrary size is investigated using GLMT. • The BSCs of the Bessel pincer light-sheet are calculated using ASDM and VSWFs. • The incident, scattering, internal and near-surface fields are numerically analyzed. • The absorption and extinction efficiencies are analyzed. • The influences of the scaling parameter and order of the Bessel pincer light-sheet are discussed. The scattering of a non-paraxial Bessel pincer light-sheet by a dielectric sphere of arbitrary size is studied in the framework of generalized Lorenz-Mie theory (GLMT). The electrical field of the Bessel pincer light-sheet is expanded using the vector angular spectrum decomposition method (VASDM), and its beam shape coefficients (BSCs) are derived using the method of multipole expansion and vector spherical wave functions (VSWF). By this way, the incident field, scattering field and near-surface field, and absorption and extinction efficiency factors are numerically calculated. Also, the effects of the beam order, scaling parameter, and polarization are mainly discussed. Numerical results represent that the intensity distribution of incident field, scattering field and near-surface field is intensely sensitive to the scaling parameters and the beam order. For the incident field, the bigger the order, the smaller the bending angle, and the closer the focus is to the source. By contrast, for the scattering and total field, the bigger the order, the larger the bending angle, and the farther the focus is to the source. Such results have potential applications in the imaging around steep corners and particle manipulation applications with minimal obstruction by particles. [ABSTRACT FROM AUTHOR]

• The optical resonance scattering of a dielectric lossless sphere of arbitrary size illuminated by a polarized Airy beam is studied using the GLMT. • The BSCs of the polarized Airy beams are calculated using VASDM and VSWFs. • The influences of beam polarization, attenuation parameter γ and transverse scale ω 0 of the incident Airy beam are discussed. • The scattering and extinction, "resonance" and "interference" efficiencies are examined under different parameters. • The scattering efficiency for a perfectly conducting sphere, the normalized far-field scattering intensity and its resonance counterpart are calculated and plotted. The optical resonance scattering of a dielectric sphere of arbitrary size illuminated by a polarized Airy beam is studied using the generalized Lorenz–Mie theory (GLMT). The electric field is derived using the vector angular spectrum decomposition method (VASDM). The beam shape coefficients (BSCs) are obtained using the multipole expansion method involving vector spherical wave functions (VSWFs). The resonance scattering characteristics are calculated using the GLMT by subtracting a non-resonant background of a perfectly conducting impenetrable sphere. The effects of beam polarization (i.e., linear, circular, radial, azimuthal, and mixed), the attenuation parameter γ and the dimensionless transverse scale kω 0 of the incident Airy beam on the scattering and extinction, "resonance" and "interference" efficiencies are examined. Moreover, the scattering efficiency for a perfectly conducting sphere as well as the three-dimensional (3D) scattering directivity patterns of the normalized dimensionless far-field scattering intensity and its resonance counterpart are calculated and plotted. The analysis of the resonance scattering shows that the energy efficiency is not the mere sum of resonance and perfectly conducting background terms; there is an interference between the two denoted by Q s c a i n t e r f , which strongly affects the resonance extinction and scattering efficiencies. The results presented here are of some importance in studying the optical resonance scattering of polarized Airy beams in applications involving imaging, particle sizing, radiation forces and torques to name a few areas of research. [ABSTRACT FROM AUTHOR]

• The scattering of a non-paraxial Bessel light-sheet by a sphere of arbitrary size is investigated using GLMT. • The BSCs of the Bessel light-sheet are calculated using ASDM and VSWFs. • The incident, internal and near-surface fields are numerically calculated. • The absorption and extinction efficiencies are analyzed. • The influences of the order and half-cone angle of the Bessel light-sheet are discussed. The scattering of a non-paraxial Bessel light-sheet by a sphere of arbitrary size is studied in framework of generalized Lorenz-–Mie theory (GLMT). The electrical fields of the Bessel light-sheet are expanded using the vector angular spectrum decomposition method (VASDM), and the beam shape coefficients (BSCs) of the Bessel light-sheet are derived using the method of multipole expansion and vector spherical wave functions (VSWF). The internal and near-surface fields, and absorption and extinction efficiency factors are numerically calculated when a Bessel light-sheet is incident, and the effects of beam's order, and half-cone angle are mainly discussed. Numerical results show that there is strong point convergence in the forward scattering region under the incident of a Bessel light-sheet, and the internal and near-surface fields of Bessel light-sheet are very sensitive to the beam's order, half-cone angle, etc. Such results have potential applications in the super-resolution imaging using a light-sheet microscopy. [ABSTRACT FROM AUTHOR]

• The optical radiation force and torque exerted on a perfect electromagnetic conductor (PEMC) sphere by an arbitrary-shaped optical polarized beam based on the generalized Lorenz-Mie theory (GLMT). • The co-polarized, cross-polarized, and interference components of the optical radiation force and torque are studied. • Both the longitudinal and the transversal optical radiation force and torque are analyzed and discussed. • The effects from the beam parameters (the order and the hale-cone of the Bessel beam) and particle parameters (the dimensionless size parameter and admittance parameter of the PEMC sphere) are analyzed. Following the previous work [Journal of Quantitative Spectroscopy & Radiative Transfer 281 (2022) 108101], which studied the scattering of an arbitrary-shaped optical polarized beam by a perfect electromagnetic conductor (PEMC) sphere, this paper is devoted to the optical radiation force (OF) and spin torque (OST) exerted on a PEMC sphere by an arbitrary-shaped optical polarized beam based on the generalized Lorenz-Mie theory (GLMT) frame. The analytical expressions of OF and OST on a PEMC sphere are derived according to the multipole expansion method (MEM) and angular spectrum decomposition method (ASDM). The numerical results of the OF and OST and their co-polarized, cross-polarized, and interference components expound on the influence of the particle parameters (admittance parameter M and dimensionless size parameter k a) and the beam parameters (polarization, order l , and half-cone angle α 0). The negative axial OF and the negative axial reverse OST that are sensitive to the α 0 and the polarization states of the Bessel beam are highlighted. Besides, the resonance phenomenon when the high order Bessel beam with a larger α 0 illuminates the PEMC (AEMC) is discussed and analyzed. The absorptive PEMC (AEMC) sphere with losses M i is also paid attention to. And the transversal OF and OST are discussed, emphasizing the vortex characteristics which are sensitive to the M and beam parameters. The above findings have broad application prospects in optical spanners, microparticle manipulation, and optical tweezers. [ABSTRACT FROM AUTHOR]

• Optical torque exerted on an absorptive dielectric sphere of arbitrary size illuminated by a polarized Airy light-sheet is investigated using GLMT. • The negative optical torque is particularly emphasized. • The influence of the transverse scale parameter w 0 and attenuation parameter y of the Airy light-sheet on the torque is discussed. Based on the generalized Lorenz-Mie theory (GLMT) and the angular spectrum decomposition method (ASDM), we calculate the time-averaged optical (spin) torque (OST) exerted on an absorptive dielectric sphere of arbitrary size illuminated by a TM polarized Airy light-sheet, and the negative optical torque is particularly emphasized. The influence of the transverse scale parameter w 0 and attenuation parameter γ of the Airy light-sheet on the torque is discussed. The numerical results show that both w 0 and γ have impact on the amplitude and spatial distributions of the OST. Furthermore, the OST amplitude depends on the position of the sphere in the transverse plane of wave propagation. In addition, the OST for a TE-polarized Airy light-sheet illuminating the absorptive dielectric sphere vanishes due to some symmetry considerations related to the vertical polarization property of the electric field vector. The results are of some practical significance for the development of Airy light-sheet based optical rotation of a suspended particle in light-sheet tweezers. [ABSTRACT FROM AUTHOR]

• The internal and near-surface fields for a charged sphere by a vector Bessel beam is investigated in the framework of GLMT. • The effects of the surface charge, polarization, order, and half-cone angle are discussed. • The local enhancements of internal and near-surface fields are analyzed. The interaction of an axicon-generated vector Bessel beam (AGVBB) with a charged sphere is investigated in the framework of generalized Lorenz–Mie theory (GLMT). The incident, internal, and scattered fields are expanded using vector spherical wave functions (VSWFs), beam shape coefficients (BSCs), and internal and scattered coefficients. An analytical expressions of beam shape coefficients (BSCs), which are derived using angular spectrum decomposition method (ASDM), are given. The internal and scattered coefficients are derived by considering the boundary conditions. The internal and near-surface electric fields of a charged sphere illuminated by AVGBBs are numerical calculated, and the effects of polarization, order of beam, half-cone angle are mainly discussed. The results are compared with that for neutral particles. The effect of the surface charge are discussed by the comparison of the results for charged spheres with that for neutral particles. Numerical results show that the internal and near-surface fields are sensitive to the surface charge. The internal fields and the near-surface fields can be locally enhanced. Internal and near-surface fields, especially its local enhancement, are very sensitive to the beam parameters, including polarization, order, half-cone angle, etc. [ABSTRACT FROM AUTHOR]