The Experts below are selected from a list of 156768 Experts worldwide ranked by ideXlab platform
Xin-qing Sheng - One of the best experts on this subject based on the ideXlab platform.
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Computation of radiation Pressure Force exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beams using MLFMA.
Optics Express, 2016Co-Authors: Minglin Yang, Kuan Fang Ren, Xin-qing ShengAbstract:Due to special characteristics of nondiffraction and self reconstruction, the Bessel beams have attracted wide attention in optical trapping and appear to be a dramatic alternative to Gaussian beams. We present in this paper an efficient approach based on the surface integral equations (SIE) to compute the radiation Pressure Force (RPF) exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beam (HOBVB). The incident beam is described by vector expressions perfectly satisfy Maxwell's equations. The problem is formulated with the combined tangential formulation (CTF) and solved iteratively with the aid of the multilevel fast multipole algorithm (MLFMA). Then RPF is computed by vector flux of the Maxwell's stress tensor over a spherical surface tightly enclosing the particle and analytical expression for electromagnetic fields of incident beam in near region are used. The numerical predictions are compared with the results of the rigorous method for spherical particle to validate the accuracy of the approach. Some numerical results on relative large particles of complex shape, such as biconcave cell-like particles with different geometry parameters are given, showing powerful capability of our approach. These results are expected to provide useful insights into the RPF exerted on complex shaped particles by HOBVB.
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Computation of radiation Pressure Force exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beams using MLFMA
Optics Express, 2016Co-Authors: Minglin Yang, Kuan Fang Ren, Xin-qing ShengAbstract:Due to special characteristics of nondiffraction and self reconstruction, the Bessel beams have attracted wide attention in optical trapping and appear to be a dramatic alternative to Gaussian beams. We present in this paper an efficient approach based on the surface integral equations (SIE) to compute the radiation Pressure Force (RPF) exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beam (HOBVB). The incident beam is described by vector expressions perfectly satisfy Maxwell's equations. The problem is formulated with the combined tangential formulation (CTF) and solved iteratively with the aid of the multilevel fast multipole algorithm (MLFMA). Then RPF is computed by vector flux of the Maxwell's stress tensor over a spherical surface tightly enclosing the particle and analytical expression for electromagnetic fields of incident beam in near region are used. The numerical predictions are compared with the results of the rigorous method for spherical particle to validate the accuracy of the approach. Some numerical results on relative large particles of complex shape, such as biconcave cell-like particles with different geometry parameters are given, showing powerful capability of our approach. These results are expected to provide useful insights into the RPF exerted on complex shaped particles by HOBVB. (C) 2016 Optical Society of America
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Fast computation of radiation Pressure Force exerted by multiple laser beams on red blood cell-like particles
Advanced Laser Manufacturing Technology, 2016Co-Authors: Ming-jiang Gou, Minglin Yang, Xin-qing ShengAbstract:Mature red blood cells (RBC) do not contain huge complex nuclei and organelles, makes them can be approximately regarded as homogeneous medium particles. To compute the radiation Pressure Force (RPF) exerted by multiple laser beams on this kind of arbitrary shaped homogenous nano-particles, a fast electromagnetic optics method is demonstrated. In general, based on the Maxwell’s equations, the matrix equation formed by the method of moment (MOM) has many right hand sides (RHS’s) corresponding to the different laser beams. In order to accelerate computing the matrix equation, the algorithm conducts low-rank decomposition on the excitation matrix consisting of all RHS’s to figure out the so-called skeleton laser beams by interpolative decomposition (ID). After the solutions corresponding to the skeletons are obtained, the desired responses can be reconstructed efficiently. Some numerical results are performed to validate the developed method.
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prediction of radiation Pressure Force exerted on moving particles by the two level skeletonization
Optics Express, 2014Co-Authors: Xin-qing ShengAbstract:A fast full-wave method for computing radiation Pressure Force (RPF) exerted by shaped light beams on moving particles is presented. The problem of evaluating RPF exerted on a moving particle by a single excitation beam is converted into that of computing RPF’s exerted on a static particle by multiple beams. The discretization of different beams leads to distinct right hand sides (RHS’s) for the matrix system. To avoid solving each RHS by the brute-Force manner, the algorithm conducts low-rank decomposition on the excitation matrix consisting of all RHS’s to figure out the so-called skeleton light beams by interpolative decomposition (ID). The peak memory requirement of the skeletonization is a bottle-neck if the particle is large. A two-level skeletonization scheme is proposed to solve this problem. Some numerical experiments on arbitrarily shaped homogeneous particles are performed to illustrate the performance and capability of the developed method.
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Computation of radiation Pressure Force on arbitrary shaped homogenous particles by multilevel fast multipole algorithm.
Optics Letters, 2013Co-Authors: Minglin Yang, Ming-jiang Gou, Kuan Fang Ren, Xin-qing ShengAbstract:A full-wave numerical method based on the surface integral equation for computing radiation Pressure Force (RPF) exerted by a shaped light beam on arbitrary shaped homogenous particles is presented. The multilevel fast multipole algorithm is employed to reduce memory requirement and to improve its capability. The resultant matrix equation is solved by using an iterative solver to obtain equivalent electric and magnetic currents. Then RPF is computed by vector flux of the Maxwell’s stress tensor over a spherical surface tightly enclosing the particle. So the analytical expressions for electromagnetic fields of incident beam in near region are used. Some numerical results are performed to illustrate the validity and capability of the developed method. Good agreements between our method and the Lorenz–Mie theory for spherical and small spheroidal particle are found while our method has powerful capability for computing RPF of any shaped beam on a relatively large particle of complex shape. Tests for ellipsoidal and red blood cell-like particles illuminated by Gaussian beam have shown that the size of the particle can be as large as 50–100 wavelengths, respectively, for the relative refractive of 1.33 and 1.1.
Kuan Fang Ren - One of the best experts on this subject based on the ideXlab platform.
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Computation of radiation Pressure Force exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beams using MLFMA.
Optics Express, 2016Co-Authors: Minglin Yang, Kuan Fang Ren, Xin-qing ShengAbstract:Due to special characteristics of nondiffraction and self reconstruction, the Bessel beams have attracted wide attention in optical trapping and appear to be a dramatic alternative to Gaussian beams. We present in this paper an efficient approach based on the surface integral equations (SIE) to compute the radiation Pressure Force (RPF) exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beam (HOBVB). The incident beam is described by vector expressions perfectly satisfy Maxwell's equations. The problem is formulated with the combined tangential formulation (CTF) and solved iteratively with the aid of the multilevel fast multipole algorithm (MLFMA). Then RPF is computed by vector flux of the Maxwell's stress tensor over a spherical surface tightly enclosing the particle and analytical expression for electromagnetic fields of incident beam in near region are used. The numerical predictions are compared with the results of the rigorous method for spherical particle to validate the accuracy of the approach. Some numerical results on relative large particles of complex shape, such as biconcave cell-like particles with different geometry parameters are given, showing powerful capability of our approach. These results are expected to provide useful insights into the RPF exerted on complex shaped particles by HOBVB.
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Computation of radiation Pressure Force exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beams using MLFMA
Optics Express, 2016Co-Authors: Minglin Yang, Kuan Fang Ren, Xin-qing ShengAbstract:Due to special characteristics of nondiffraction and self reconstruction, the Bessel beams have attracted wide attention in optical trapping and appear to be a dramatic alternative to Gaussian beams. We present in this paper an efficient approach based on the surface integral equations (SIE) to compute the radiation Pressure Force (RPF) exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beam (HOBVB). The incident beam is described by vector expressions perfectly satisfy Maxwell's equations. The problem is formulated with the combined tangential formulation (CTF) and solved iteratively with the aid of the multilevel fast multipole algorithm (MLFMA). Then RPF is computed by vector flux of the Maxwell's stress tensor over a spherical surface tightly enclosing the particle and analytical expression for electromagnetic fields of incident beam in near region are used. The numerical predictions are compared with the results of the rigorous method for spherical particle to validate the accuracy of the approach. Some numerical results on relative large particles of complex shape, such as biconcave cell-like particles with different geometry parameters are given, showing powerful capability of our approach. These results are expected to provide useful insights into the RPF exerted on complex shaped particles by HOBVB. (C) 2016 Optical Society of America
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analysis of radiation Pressure Force exerted on a biological cell induced by high order bessel beams using debye series
Journal of Quantitative Spectroscopy & Radiative Transfer, 2013Co-Authors: Kuan Fang Ren, Xiange Han, Lixin Guo, Shuxi GongAbstract:Debye series expansion (DSE) is employed to the analysis of radiation Pressure Force (RPF) exerted on biological cells induced by high-order Bessel beams (BB). The beam shape coefficients (BSCs) for high-order Bessel beams are calculated using analytical expressions obtained by the integral localized approximation (ILA). Different types of cells, including a real Chinese Hamster Ovary (CHO) cell and a lymphocyte which are respectively modeled by a coated and five-layered sphere, are considered. The RPF induced by high-order Bessel beams is compared with that by Gaussian beams and zeroth-order Bessel beams, and the effect of different scattering processes on RPF is studied. Numerical calculations show that high-order Bessel beams with zero central intensity can also transversely trap particle in the beam center, and some scattering processes can provide longitudinal pulling Force.
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Computation of radiation Pressure Force on arbitrary shaped homogenous particles by multilevel fast multipole algorithm.
Optics Letters, 2013Co-Authors: Minglin Yang, Ming-jiang Gou, Kuan Fang Ren, Xin-qing ShengAbstract:A full-wave numerical method based on the surface integral equation for computing radiation Pressure Force (RPF) exerted by a shaped light beam on arbitrary shaped homogenous particles is presented. The multilevel fast multipole algorithm is employed to reduce memory requirement and to improve its capability. The resultant matrix equation is solved by using an iterative solver to obtain equivalent electric and magnetic currents. Then RPF is computed by vector flux of the Maxwell’s stress tensor over a spherical surface tightly enclosing the particle. So the analytical expressions for electromagnetic fields of incident beam in near region are used. Some numerical results are performed to illustrate the validity and capability of the developed method. Good agreements between our method and the Lorenz–Mie theory for spherical and small spheroidal particle are found while our method has powerful capability for computing RPF of any shaped beam on a relatively large particle of complex shape. Tests for ellipsoidal and red blood cell-like particles illuminated by Gaussian beam have shown that the size of the particle can be as large as 50–100 wavelengths, respectively, for the relative refractive of 1.33 and 1.1.
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Theoretical prediction of radiation Pressure Force exerted on a spheroid by an arbitrarily shaped beam.
Physical Review E, 2007Co-Authors: Kuan Fang Ren, Gérard Gouesbet, Xiaoshu Cai, Gérard GréhanAbstract:A rigorous theory is developed to predict the radiation Pressure Force (RPF) exerted on a spheroid by an arbitrarily oriented and located shaped beam. Analytical expressions of RPF are derived for a homogeneous spheroid, which can be prolate or oblate, transparent or absorbing. Exemplifying calculations are performed and RPF calculations for spheroids are compared to RPF calculations for spheres. The ``Optical Stretcher'' is also numerically simulated to study the RPF exerted on a red blood cell during its deformation.
Minglin Yang - One of the best experts on this subject based on the ideXlab platform.
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Computation of radiation Pressure Force exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beams using MLFMA.
Optics Express, 2016Co-Authors: Minglin Yang, Kuan Fang Ren, Xin-qing ShengAbstract:Due to special characteristics of nondiffraction and self reconstruction, the Bessel beams have attracted wide attention in optical trapping and appear to be a dramatic alternative to Gaussian beams. We present in this paper an efficient approach based on the surface integral equations (SIE) to compute the radiation Pressure Force (RPF) exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beam (HOBVB). The incident beam is described by vector expressions perfectly satisfy Maxwell's equations. The problem is formulated with the combined tangential formulation (CTF) and solved iteratively with the aid of the multilevel fast multipole algorithm (MLFMA). Then RPF is computed by vector flux of the Maxwell's stress tensor over a spherical surface tightly enclosing the particle and analytical expression for electromagnetic fields of incident beam in near region are used. The numerical predictions are compared with the results of the rigorous method for spherical particle to validate the accuracy of the approach. Some numerical results on relative large particles of complex shape, such as biconcave cell-like particles with different geometry parameters are given, showing powerful capability of our approach. These results are expected to provide useful insights into the RPF exerted on complex shaped particles by HOBVB.
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Computation of radiation Pressure Force exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beams using MLFMA
Optics Express, 2016Co-Authors: Minglin Yang, Kuan Fang Ren, Xin-qing ShengAbstract:Due to special characteristics of nondiffraction and self reconstruction, the Bessel beams have attracted wide attention in optical trapping and appear to be a dramatic alternative to Gaussian beams. We present in this paper an efficient approach based on the surface integral equations (SIE) to compute the radiation Pressure Force (RPF) exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beam (HOBVB). The incident beam is described by vector expressions perfectly satisfy Maxwell's equations. The problem is formulated with the combined tangential formulation (CTF) and solved iteratively with the aid of the multilevel fast multipole algorithm (MLFMA). Then RPF is computed by vector flux of the Maxwell's stress tensor over a spherical surface tightly enclosing the particle and analytical expression for electromagnetic fields of incident beam in near region are used. The numerical predictions are compared with the results of the rigorous method for spherical particle to validate the accuracy of the approach. Some numerical results on relative large particles of complex shape, such as biconcave cell-like particles with different geometry parameters are given, showing powerful capability of our approach. These results are expected to provide useful insights into the RPF exerted on complex shaped particles by HOBVB. (C) 2016 Optical Society of America
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Fast computation of radiation Pressure Force exerted by multiple laser beams on red blood cell-like particles
Advanced Laser Manufacturing Technology, 2016Co-Authors: Ming-jiang Gou, Minglin Yang, Xin-qing ShengAbstract:Mature red blood cells (RBC) do not contain huge complex nuclei and organelles, makes them can be approximately regarded as homogeneous medium particles. To compute the radiation Pressure Force (RPF) exerted by multiple laser beams on this kind of arbitrary shaped homogenous nano-particles, a fast electromagnetic optics method is demonstrated. In general, based on the Maxwell’s equations, the matrix equation formed by the method of moment (MOM) has many right hand sides (RHS’s) corresponding to the different laser beams. In order to accelerate computing the matrix equation, the algorithm conducts low-rank decomposition on the excitation matrix consisting of all RHS’s to figure out the so-called skeleton laser beams by interpolative decomposition (ID). After the solutions corresponding to the skeletons are obtained, the desired responses can be reconstructed efficiently. Some numerical results are performed to validate the developed method.
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Computation of radiation Pressure Force on arbitrary shaped homogenous particles by multilevel fast multipole algorithm.
Optics Letters, 2013Co-Authors: Minglin Yang, Ming-jiang Gou, Kuan Fang Ren, Xin-qing ShengAbstract:A full-wave numerical method based on the surface integral equation for computing radiation Pressure Force (RPF) exerted by a shaped light beam on arbitrary shaped homogenous particles is presented. The multilevel fast multipole algorithm is employed to reduce memory requirement and to improve its capability. The resultant matrix equation is solved by using an iterative solver to obtain equivalent electric and magnetic currents. Then RPF is computed by vector flux of the Maxwell’s stress tensor over a spherical surface tightly enclosing the particle. So the analytical expressions for electromagnetic fields of incident beam in near region are used. Some numerical results are performed to illustrate the validity and capability of the developed method. Good agreements between our method and the Lorenz–Mie theory for spherical and small spheroidal particle are found while our method has powerful capability for computing RPF of any shaped beam on a relatively large particle of complex shape. Tests for ellipsoidal and red blood cell-like particles illuminated by Gaussian beam have shown that the size of the particle can be as large as 50–100 wavelengths, respectively, for the relative refractive of 1.33 and 1.1.
Mayeul Arminjon - One of the best experts on this subject based on the ideXlab platform.
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Gravitation as a Pressure Force: a scalar ether theory
arXiv: General Physics, 2011Co-Authors: Mayeul ArminjonAbstract:If the presence of a gravitational field breaks the Lorentz symmetry valid for special relativity, an "absolute motion" might be detectable. We summarize a scalar theory of gravity with a such "ether", which starts from a tentative interpretation of gravity as a Pressure Force. The theory also admits that our physical standards of space and time are affected by gravitation similarly as they are affected by a uniform motion. General motion is governed by an extension of Newton's second law to the curved space-time which is thus obtained. Together with the scalar field equation of the theory, this leads to a true conservation equation for the total energy. The law of motion also leads to an alternative 4-component equation governing the dynamics of a continuum in terms of its energy-momentum tensor. That new equation implies that mass conservation is obtained as a limiting behaviour for a weak and slowly varying gravitational field and/or at a low Pressure. In the presence of the Lorentz Force field, the new dynamical equation gives the second group of the gravitationally-modified Maxwell equations in the investigated theory. This is consistent with the geometrical optics of the theory as governed by the proposed extension of Newton's second law. The theory has the correct Newtonian limit; it predicts Schwarzschild's exterior metric of general relativity and geodesic motion in the static situation with spherical symmetry. A post-Newtonian approximation of this theory shows that no preferred-frame effect occurs for photons at the (first) post-Newtonian approximation. It is argued that the existence of preferred-frame effects in celestial mechanics, comparable in magnitude with the "relativistic" effects, does not a priori invalidate the theory.
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A theory of gravity as a Pressure Force. II. Lorentz contraction and "relativistic" effects
arXiv: General Relativity and Quantum Cosmology, 2006Co-Authors: Mayeul ArminjonAbstract:In a foregoing paper, gravity has been interpreted as the Pressure Force exerted on matter at the scale of elementary particles by a perfect fluid. Under the condition that Newtonian gravity must be recovered in the incompressible case, a scalar field equation has thus been proposed for gravity, giving a new theory in the compressible case. Here the theory is reinterpreted so as to describe the relativistic effects, by extending the Lorentz-Poincar\'e interpretation of special relativity which is first recalled. Gravitational space-contraction and time-dilatation are postulated, as a consequence of the principle of local equivalence between the effects of motion and gravitation. The space-time metric (expressing the proper time along a trajectory) is hence curved also in the proposed theory. As the result of a modified Newton law, it is proved that free test particles follow geodesic lines of this metric. In the spherical static situation, Schwarzschild's exterior metric is exactly recovered and with it the experimental support of general relativity, but the interior solution as well as the problematic of singularities are different in the proposed theory, e.g. the radius of the body cannot be smaller than the Schwarzschild radius.
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Scalar theory of gravity as a Pressure Force
arXiv: General Physics, 1997Co-Authors: Mayeul ArminjonAbstract:The construction of this theory starts with Newtonian space-time and a tentative interpretation of gravity as Archimedes' thrust exerted on matter at the scale of elementary particles by an imagined perfect fluid or ether. This leads to express the gravity acceleration by a simple formula in which the "ether Pressure" pe plays the role of the Newtonian potential. The instantaneous propagation of Newtonian gravity is obtained with an incompressible ether, giving a field equation for pe. For a compressible ether, this equation holds in the static case and results in a non-linear influence of the mass distribution. The extension of the field equation to non-static situations follows the lines of acoustics and leads to gravitational (Pressure) waves. To account for metric effects, first the modern version of the Lorentz-Poincare interpretation of special relativity is summarized. Then Einstein's equivalence principle (EP) is seen as a correspondence between the metric effects of gravity and those of uniform motion with respect to the ether : a gravitational contraction (dilation) of space (time) standards is assumed, and it implies geodesic motion for test particles in a static field. The same field equation is now expressed in terms of the physical space and time metrics in the frame of ether; since both metrics depend on pe due to the EP, it becomes non-linear in pe. In the spherical static situation, Schwarzschild's exterior metric is predicted, but the interior metric differs from GR, though it agrees with the EP. Since Pressure produces gravitation also in the proposed theory, no equilibrium is possible for very massive objects. But the gravitational collapse in free fall does not lead to any singularity. Moreover, gravitational waves, and even shock ones, can exist in vacuo also with spherical symmetry.
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A theory of gravity as a Pressure Force. I: Newtonian space and time
1993Co-Authors: Mayeul ArminjonAbstract:Gravity is interpreted as the Pressure Force exerted on matter at the scale of elementary particles by a perfect fluid, the rest frame of which defines the inertial frame. The first task is thus to extend newtonian mechanics so that it allows a deformation of the inertial frame. An application to the stability study of an expanding, rigid or contracting universe is given. The Pressure of the inertial fluid is equivalent to a mass Force, if the elementary particles have the same (average) mass density, dependig only on the fluid Pressure. Hence stable particles should be permanent flows in the flkuid, such as vortices. Gravity should be only the macroscopic part of the Pressure Force
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A theory of gravity as a Pressure Force. II: Lorentz contraction and «relativistic» effects
1993Co-Authors: Mayeul ArminjonAbstract:In a foregoing paper, gravity has been interpreted as the Pressure Force exerted on matter at the scale of elementary particles by a perfect fluid. Under the condition that Newtonian gravity must be recovered in the incompressible case, a scalar field equation has thus been proposed for gravity, giving a new theory in the compressible case. Here the theory is reinterpreted so as to describe the relativistic effects, by extending the Lorentz-Poincarre interpretation of special relativity which is first recalled. Gravitational space-contraction and time-dilatation are postulated, as a consequence of the principle of local equivalence between the effects of motion and gravitation
Paul Lukowicz - One of the best experts on this subject based on the ideXlab platform.
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Smart Textiles - Textile Pressure Force Mapping
Smart Textiles, 2017Co-Authors: Bo Zhou, Paul LukowiczAbstract:While much effort in smart textile technology development has been put on acquiring biomedical signals such as ECG/EMG or tissue bioimpedance, an important alternative is mapping the Pressure which is applied to the textile substrate itself. The modality has inspired researchers to instrument a wide variety of daily items and wearable garments for interactive controlling and activity monitoring in the recent years. To offer a guideline for implementing such systems, this chapter will introduce textile-based Pressure Force mapping sensing technology, from comparisons with other smart textile technologies to sensing principles, driving circuitry and finally several application examples.