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Stokes parameters of optical singularities of random electromagnetic beams
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作者 李建龙 朱世富 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期288-292,共5页
In this paper, the relation between the spectral degree of coherence and degree of polarization of random electromagnetic beams is derived by the Stokes parameters. And the concept of polarization singularity is exten... In this paper, the relation between the spectral degree of coherence and degree of polarization of random electromagnetic beams is derived by the Stokes parameters. And the concept of polarization singularity is extended from spatially fully coherent beams to partially coherent electromagnetic beams. Theoretical analysis shows that correlation vortices are linearly polarized singularities. The results are illustrated by numerical examples. 展开更多
关键词 stokes parameters optical singularities electromagnetic beams
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Experimental Measurement of the Generalized Stokes Parameters of a Radially Polarized Random Electromagnetic Beam
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作者 Yongxin Liu Songjie Luo +1 位作者 Jixiong Puri Zenghui Gao 《Journal of Electromagnetic Analysis and Applications》 2016年第6期109-114,共7页
Utilizing the Young’s double slits and Mach-Zehnder interferometer, we proposed an experimental method to measure the generalized Stokes parameters of a radially polarized random electromagnetic beam. After the parti... Utilizing the Young’s double slits and Mach-Zehnder interferometer, we proposed an experimental method to measure the generalized Stokes parameters of a radially polarized random electromagnetic beam. After the partially coherent beam propagating through the Young’s double slits, the interference fringe is obtained by the help of a Mach-Zehnder interferometer consisting of apertures, quarter-wave plates and polarizers. The electric cross-spectral density matrix is detected by the coherence degree of interference fringe and the density of each single slit. The generalized Stokes parameters can be obtained from the electric cross-spectral density matrix. This experiment measures the generalized Stokes parameters of the random electromagnetic beam successfully. The results show that the spectral degree of coherence for copolarized cases (xx and yy) is similar with that for cross-polaried cases (xy and yx) for the radially polarized random electromagnetic beam. This method will help us determine the change of the polarization and coherence of the light in propagation by detecting the change of the generalized Stokes parameters. 展开更多
关键词 Generalized stokes parameters Electric Cross-Spectral Density Matrix Young’s Double Slits Mach-Zehnder Interferometer Radially Polarized Stochastic Electromagnetic Beam
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Statistical characteristics of the normalized Stokes parameters 被引量:2
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作者 LIU Tao WANG XueSong XIAO ShunPing 《Science in China(Series F)》 2008年第10期1594-1606,共13页
The statistical properties of the normalized Stokes parameters in a Gaussian stochastic plane wave field are described in detail. Via the expression of the three normalized Stokes parameters, the mean, variance, and h... The statistical properties of the normalized Stokes parameters in a Gaussian stochastic plane wave field are described in detail. Via the expression of the three normalized Stokes parameters, the mean, variance, and high-order moments are calculated, which simplify C. Brosseau's results. The new dispersion, normalized contrast function, skewness, and kurtosis are defined to describe the non-Gaussian distribution characteristics, which can be applied to Gaussian wave fields relating to depolarization of light by a spatially random medium. 展开更多
关键词 instantaneous polarization stokes vector statistical analysis the normalized stokes parameters
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Application of the Phase Difference of the Variable Components of the Stokes Vector for Measuring Linear Birefringence
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作者 Igor Linchevskyi Ira Mizyunska 《Journal of Physical Science and Application》 2017年第5期67-73,共7页
To investigate the magneto-optical properties of new materials, a method for measuring linear birefringence based on a change in the initial phase of the variable component of the signal at the output of the photopola... To investigate the magneto-optical properties of new materials, a method for measuring linear birefringence based on a change in the initial phase of the variable component of the signal at the output of the photopolarimeter was developed. For this purpose, there was used a magneto-optical modulator, at the output of which the variable components of the Stokes vector have different initial phases. The advantage of the method is the absence of rotating optical elements, the independence of the measurement results with a change in the intensity in the optical circuit, which simplifies the measurement process. As an example, the results of measurements of magnetic linear birefringence in a film of yttrium garnet ferrite are given. The minimal increment of the phase shift between optical waves polarized along orthogonal linear polarizations (the Cotton-Mouton effect), which was measured in this experiment is 0.01 deg. 展开更多
关键词 Linear birefringence photopolarimeter stokes parameters magneto-optical crystal.
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Error analysis and Stokes parameter measurement of rotating quarter-wave plate polarimeter 被引量:1
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作者 支丹丹 李健军 +3 位作者 高冬阳 翟文超 黄雄豪 郑小兵 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期242-247,共6页
In this paper, we present a simple Stokes parameter measurement method for a rotating quarter-wave plate polarimeter. This method is used to construct a model to describe the principle of how the magnitudes of errors ... In this paper, we present a simple Stokes parameter measurement method for a rotating quarter-wave plate polarimeter. This method is used to construct a model to describe the principle of how the magnitudes of errors influence the deviation of the output light Stokes parameter, on the basis of accuracy analysis of the retardance error of the quarter-wave plate, the misalignment of the analyzing polarizer, and the phase shift of the measured signals, which will help us to determine the magnitudes of these errors and then to acquire the correct results of Stokes parameters. The method is validated by the experiments on left-handed circularly polarized and linear horizontal polarization beams. With the improved method, the maximum measurement deviations of Stokes parameters for these two different polarized states are reduced from 2.72% to 2.68%, and from 3.83% to 1.06% respectively. Our results demonstrate that the proposed method can be used as a promising approach to Stokes parameter measurement for a rotating quarter-wave plate polarimeter. 展开更多
关键词 POLARIZATION stokes parameter detection POLARIMETER
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Diabetes Type 2: Poincaré Data Preprocessing for Quantum Machine Learning 被引量:1
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作者 Daniel Sierra-Sosa Juan D.Arcila-Moreno +1 位作者 Begonya Garcia-Zapirain Adel Elmaghraby 《Computers, Materials & Continua》 SCIE EI 2021年第5期1849-1861,共13页
Quantum Machine Learning(QML)techniques have been recently attracting massive interest.However reported applications usually employ synthetic or well-known datasets.One of these techniques based on using a hybrid appr... Quantum Machine Learning(QML)techniques have been recently attracting massive interest.However reported applications usually employ synthetic or well-known datasets.One of these techniques based on using a hybrid approach combining quantum and classic devices is the Variational Quantum Classifier(VQC),which development seems promising.Albeit being largely studied,VQC implementations for“real-world”datasets are still challenging on Noisy Intermediate Scale Quantum devices(NISQ).In this paper we propose a preprocessing pipeline based on Stokes parameters for data mapping.This pipeline enhances the prediction rates when applying VQC techniques,improving the feasibility of solving classification problems using NISQ devices.By including feature selection techniques and geometrical transformations,enhanced quantum state preparation is achieved.Also,a representation based on the Stokes parameters in the PoincaréSphere is possible for visualizing the data.Our results show that by using the proposed techniques we improve the classification score for the incidence of acute comorbid diseases in Type 2 Diabetes Mellitus patients.We used the implemented version of VQC available on IBM’s framework Qiskit,and obtained with two and three qubits an accuracy of 70%and 72%respectively. 展开更多
关键词 Quantum machine learning data preprocessing stokes parameters Poincarésphere
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Polarization state measurement based on photoelastic modulation
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作者 高婷婷 韩慧莲 《Journal of Measurement Science and Instrumentation》 CAS 2014年第4期68-73,共6页
Polarization coding is a specific encoding method by using the polarization state of optical signal carrying coded in- formation. It focuses on nonlinear effects, polarization mode dispersion and other issues in high-... Polarization coding is a specific encoding method by using the polarization state of optical signal carrying coded in- formation. It focuses on nonlinear effects, polarization mode dispersion and other issues in high-speed fiber-optic communi- cations. This paper presents a measurement method for polarization state based on elastic-optic modulator. This method not only retains the original advantages of elastic-optic modulator for polarization measurement, but also overcomes the defects of existing methods including high modulation frequency and invalid collection by using array detector. Matlab simulation and experimental verification scheme are given. The feasibility of this method is verified through theoretical analysis, and simulation and experimental results are carried out. The error analysis of the measurement results shows that the method can meet the measurement requirements and provide conditions for using the polarization encoding in high-speed communication. 展开更多
关键词 stokes parameter difference frequency modulation polarization measurement polarization encoding
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What Physics Can We Learn from Integrated Stokes Parameter Measurements Made with Polarized Electrons?
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作者 Timothy J.Gay 《Tsinghua Science and Technology》 SCIE EI CAS 2001年第5期458-468,483,共12页
关键词 What Physics Can We Learn from Integrated stokes Parameter Measurements Made with Polarized Electrons WE
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Spatially modulated polarimetry based on a vortex retarder and Fourier analysis 被引量:4
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作者 Chao Gao Bing Lei 《Chinese Optics Letters》 SCIE EI CAS CSCD 2021年第2期19-24,共6页
We report a spatially modulated polarimetry scheme by using a zero-order vortex half-wave retarder(ZVHR)and a spatial Fourier analysis method.A ZVHR is employed to analyze the input polarized light and convert it into... We report a spatially modulated polarimetry scheme by using a zero-order vortex half-wave retarder(ZVHR)and a spatial Fourier analysis method.A ZVHR is employed to analyze the input polarized light and convert it into a vectorial optical field,and an analyzer is set after the ZVHR to form an hourglass intensity pattern due to the spatial polarization modulation.Then,the input light’s Stokes parameters can be calculated by spatial Fourier analysis of the hourglass pattern with a single shot.The working principle of the polarimeter has been analyzed by the Stokes-Mueller formalism,and some quantitative measuring experiments of different polarization states have been demonstrated.The experimental results indicate that the proposed polarimeter is accurate,robust,and simple to use. 展开更多
关键词 POLARIMETRY stokes parameters vortex retarder Fourier analysis spatial modulation
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Oil spill detection on the ocean surface using hybrid polarimetric SAR imagery 被引量:2
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作者 LI HaiYan PERRIE William +1 位作者 ZHOU YuanZe HE YiJun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第2期249-257,共9页
Hybrid-polarimetric SAR(synthetic aperture radar) is a new SAR mode, with relatively simple architecture, low cost, and wide swath, which will be carried by several Earth-observing systems from now to the near future.... Hybrid-polarimetric SAR(synthetic aperture radar) is a new SAR mode, with relatively simple architecture, low cost, and wide swath, which will be carried by several Earth-observing systems from now to the near future. Here, we show how the second Stokes parameter of hybrid-polarimetric SAR can be employed to detect oil on the ocean surface using the classic well-known Otsu threshold methodology, in relation to contributions from different polarizations and dampening effects on backscatter intensity, neglecting the specific scattering mechanisms and oil types for an oil-covered surface. The detection methodology is demonstrated to be reliable in three example cases: oil-on-water experiments conducted by the Norwegian Clean Seas Association, natural oil seeps from the Gulf of Mexico, and observations from the Deep Water Horizon oil spill disaster in 2010. 展开更多
关键词 Oil spill detection Hybrid polarization Compact polarimetric SAR stokes parameters Otsu threshold
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Single-shot measurement of free-electron laser polarization at SDUV-FEL
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作者 冯冽 邓海啸 +10 位作者 张彤 冯超 陈建辉 王兴涛 兰太和 沈磊 张文艳 姚海凤 刘晓庆 刘波 王东 《Chinese Physics C》 SCIE CAS CSCD 2015年第2期91-94,共4页
In this paper, a division-of-amplitude photopolarimeter (DOAP) for measuring the polarization state of a free-electron laser (FEL) pulse is described. The incident FEL beam is divided into four separate beams, and... In this paper, a division-of-amplitude photopolarimeter (DOAP) for measuring the polarization state of a free-electron laser (FEL) pulse is described. The incident FEL beam is divided into four separate beams, and four Stokes parameters can be measured in a single-shot. In the crossed-planar undulators experiment at the Shanghai deep ultraviolet FEL test facility, this DOAP instrument constructed in house responsed accurately and timely while the polarization-state of fully coherent FEL pulses were switched, which is helpful for confirming the crossed-planar undulators technique for short-wavelength FELs. 展开更多
关键词 POLARIZATION DOAP stokes parameters seeded-FEL
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Terrain topographic inversion using single-pass polarimetric SAR image data 被引量:5
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作者 JINYaqiu LUOLin 《Science in China(Series F)》 2004年第4期490-500,共11页
The shift of polarization orientation angle y at the maximum of co-polarized or cross-polarized back-scattering signature can be used to estimate the surface slopes. It has been utilized to generate the digital elevat... The shift of polarization orientation angle y at the maximum of co-polarized or cross-polarized back-scattering signature can be used to estimate the surface slopes. It has been utilized to generate the digital elevation mapping (DEM) and terrain topography using two-pass fully polarimetric SAR or interferometric SAR (INSAR) image data. This paper presents an approach to DEM inversion by using a single pass of polarimetric SAR data. The y shift is derived, by using the Mueller matrix solution, as a function of three Stokes parameters, Ivs, Ihs, Us, which are measured by the SAR polarimetry. Using the Euler angles transformation, the orientation angle y is related to both the range and azimuth angles of the tilted surface and radar viewing geometry, as has been discussed by many authors. When only a single-pass SAR data is available, the adaptive thresholding method and image morphological thinning algorithm for linear textures are proposed to first determine the azimuth angle. Then, making use of full multi-grid algorithm, both the range and azimuth angles are utilized to solve the Poisson equation of DEM to produce the terrain topography. 展开更多
关键词 single pass fully polarimetric stokes parameter SHIFT azimuth and range angles terrain topog-raphy DEM.
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