Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes polarized.This study employs a novel split-focus plane polarimetric camera to conduct t...Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes polarized.This study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the Moon.We obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the Moon.The findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria overall.Combining the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the Moon.This study may serve as a new diagnostic tool for the Moon.展开更多
Metasurface-based polarimetry techniques have attracted lots of interests and been extensively studied in the past years,but are still hampered by narrow operating bandwidth and large crosstalk.Recently,Xian-Gang Luo&...Metasurface-based polarimetry techniques have attracted lots of interests and been extensively studied in the past years,but are still hampered by narrow operating bandwidth and large crosstalk.Recently,Xian-Gang Luo's group proposed a new method of polarization-dependent phase optimization for the design of crosstalk-free,broadband achromatic,and full Stokes imaging polarimeter,which offers a promising platform for a wide range of applications including bio-photonics and integrated optics.展开更多
A practical calibration method is proposed for instantaneous polarization radar systems.The method only needs one measurement by using a metal sphere.The distortions of system and the actual polarization scattering ma...A practical calibration method is proposed for instantaneous polarization radar systems.The method only needs one measurement by using a metal sphere.The distortions of system and the actual polarization scattering matrix(PSM)of target can be obtained.First,an instantaneous polarization radar system is presented.The system can obtain PSM by a single pulse echo.The dual-polarization antenna can transmit and receive two orthogonal polarization waves.The multilayer micro-strip patch antenna is adopted for this kind of radar system.Second,based on the multi-port network theory,the operation and system errors of instantaneous polarization radar system are analyzed.By making assumption on the cross-talk factors of antenna,distortion matrices of R and Tare derived.Finally,the calibration method based on instantaneous polarization measurement is introduced.Simulation results show the performance of this calibration method.The values of calibrated PSM are in agreement with the actual ones after calibration.展开更多
Using a polarization method, the scattering problem for a two-dimensional inclusion embedded in infinite piezoelectric/piezomagnetic matrices is investigated. To achieve the purpose, the polarization method for a two-...Using a polarization method, the scattering problem for a two-dimensional inclusion embedded in infinite piezoelectric/piezomagnetic matrices is investigated. To achieve the purpose, the polarization method for a two-dimensional piezoelectric/piezomagnetic "comparison body" is formulated. For simple harmonic motion, kernel of the polarization method reduces to a 2-D time-harmonic Green's function, which is obtained using the Radon transform. The expression is further simplified under conditions of low frequency of the incident wave and small diameter of the inclusion. Some analytical expressions are obtained. The analytical solutions for generalized piezoelectric/piezomagnetic anisotropic composites are given followed by simplified results for piezoelectric composites. Based on the latter results, two numerical results are provided for an elliptical cylindrical inclusion in a PZT-5H-matrix, showing the effect of different factors including size, shape, material properties, and piezoelectricity on the scattering cross-section.展开更多
Objective:To evaluate the effect of heat-clearing and detoxifying method on the macrophages polarization in patients with acute myocardial infarction with heat toxin syndrome after intervention.Methods:Sixty patients ...Objective:To evaluate the effect of heat-clearing and detoxifying method on the macrophages polarization in patients with acute myocardial infarction with heat toxin syndrome after intervention.Methods:Sixty patients with acute myocardial infarction and undergoing percutaneous coronary intervention with heat toxin syndrome were randomly divided into a control group and a test group with 30 cases each.The control group was given conventional treatment,and the test group was given Huanglian Jiedu Decoction,the representative of the method of clearing heat and detoxification,orally on the basis of the control group.The intervention time of both groups was 2 weeks.Comparing The Seattle Angina Pectoris Scale(SAQ)before and after treatment,creatine kinase(CK),creatine kinase MB isoenzyme(CKMB),high-sensitivity troponin I(hs-TnI),and Lipoprotein-associated phospholipaseA2(LPPLA_2)),the phenotype ratio of M1 and M2 macrophages,and observe the adverse reactions.Results:After treatment,the SAQ scores of the two groups of patients were improved,and the levels of CK,CK-MB,hs-TnI,and LP-PLA_2 decreased significantly.The scores of AS,AF,TS,and DP in the SAQ of the test group were all higher than those of the control group,and the hs-TnI and LP-PLA_2 were better than those of the control Group(P<0.05 or P<0.01).After treatment,the proportion of M1 type macrophages in the two groups of patients'macrophages decreased significantly(P<0.05 or P<0.01),the ratio of M2 type macrophages increased(P<0.05),and the M1/M2 ratio decreased.The ratio of M1/M2 in the test group of the control group was significantly lower than that of the control group(P<0.01).There were no obvious adverse reactions in both groups.Conclusions:The method of clearing heat and detoxifying has a definite effect on patients with acute myocardial infarction of heat toxin syndrome after interventional operation.It can reduce myocardial damage,improve myocardial function,and reduce inflammation.And it is safe for clinical treatment without any increasing risk of bleeding or other risk of cardiovascular events.展开更多
The vectorial structure of an optical field with hybrid states of polarization (SOP) in the near-field is studied by using the angular spectrum method of an electromagnetic beam. Physical images of the longitudinal ...The vectorial structure of an optical field with hybrid states of polarization (SOP) in the near-field is studied by using the angular spectrum method of an electromagnetic beam. Physical images of the longitudinal components of evanescent waves are illustrated and compared with those of the transverse components from the vectorial structure. Our results indicate that the relative weight integrated over the transverse plane of the evanescent wave depends strongly on the number of the polarization topological charges. The shapes of the intensity profiles of the longitudinal components are different from those of the transverse components, and it can be manipulated by changing the initial SoP of the field cross-section. The longitudinal component of evanescent wave dominates the near-field region. In addition, it also leads to three-dimensional shape variations of the optical field and the optical spin angular momentum flux density distributions.展开更多
A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous H...A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous Hamiltonian system is multiplied by a set of multiplicative functions, then the general expression of the first integral can be obtained, An example is given to illustrate the application of the results.展开更多
A novel matching method for simultaneous multi-target recognition is proposed by jointly considering target's prior scattering knowledge and the polarization parameters of radar echoes. The matching coefficients a...A novel matching method for simultaneous multi-target recognition is proposed by jointly considering target's prior scattering knowledge and the polarization parameters of radar echoes. The matching coefficients are calculated for the judgment. MATLAB simulations show that several targets can be accurately recognized simultaneously, and a high recognition probability can be achieved in Monte Carlo simulations. The total execution time can be remarkably reduced in the Field Programmable Gate Array (FPGA) implementation of the matching procedure.展开更多
A new polarization rotator based on the silica photonic crystal fiber is proposed. The proposed polarization rotator photonic crystal fiber (PR-PCF) possesses a triangle jigsaw-shape core region. The full-vector fin...A new polarization rotator based on the silica photonic crystal fiber is proposed. The proposed polarization rotator photonic crystal fiber (PR-PCF) possesses a triangle jigsaw-shape core region. The full-vector finite-element method is used to analyze the phenomenon of polarization conversion between the quasi-TE and quasi-TM modes. Numerical simulations show that the wavelengths of 1.31 μm and 1.55 μm are converted with a nearly 100% polarization conversion ratio with their matched coupling length and has a relatively strong realistic fabrication tolerance - 100 nm on the y axis and 50 nm on the x axis. The full vectorial finite difference beam propagation method is used to confirm the performance of the proposed PR-PCF.展开更多
Using discrete variational X. method within the local-density-functional theory and cluster models, the electronic structure and magnetic property or MnSh(Ce) are investigated.It is round that Sb5p state is much pola...Using discrete variational X. method within the local-density-functional theory and cluster models, the electronic structure and magnetic property or MnSh(Ce) are investigated.It is round that Sb5p state is much polarized by Ce doping.The spin moment of Sb changes from -0.06 V,in MnSh to -0.32μb, in MnSh(Ce).The interaction between Mn and doped Ce is small compared with that between Sb and Ce in MnSh(Ce).The influence to the magneto-optical Property of MnSh by the doped Ce is discussed. It is expected that the Sb-5p polarization caused by Ce will make MnSh(Ce)a promising magneto-optical material.展开更多
Detailed calculations are carried out for the electron-impact excitation cross sections from the ground state to the individual magnetic sublevels of the 1s2s^(2)2p^(3)/2 J=2 excited state of highly-charged beryllium-...Detailed calculations are carried out for the electron-impact excitation cross sections from the ground state to the individual magnetic sublevels of the 1s2s^(2)2p^(3)/2 J=2 excited state of highly-charged beryllium-like ions by using a fully relativistic distorted-wave(RDW)method.The contributions of the Breit interaction to the linear polarization of the 1s2s^(2)2p^(3)/2 J=2→1s22s2 J=0 magnetic quadrupole(M2)line are investigated systematically for the beryllium isoelectronic sequence with 42≤Z≤92.It is found that the Breit interaction depolarizes significantly the linear polarization of the M2 fluorescence radiation and that these depolarization effects increase as the incident electron energy and/or the atomic number is enlarged.展开更多
We numerically demonstrate the modulation of plasmon resonances in a metamolecule composed of metal bars and L-shaped nanoparticles by using the finite difference time domain method.Due to the dependence of electromag...We numerically demonstrate the modulation of plasmon resonances in a metamolecule composed of metal bars and L-shaped nanoparticles by using the finite difference time domain method.Due to the dependence of electromagnetic coupling on polarization of the incident light,we show that the superradiant and subradiant states can be switched from ON and OFF resonantly.These two resonances are continuously adjustable as the polarization angle of incident wave changes.This feature reveals a possibility of dynamically switching the coupled plasmon resonances of an artificial microstructure and to construct functional metamaterials,which is helpful for nanophotonic devices such as filters and optical switches.展开更多
The paper assesses how multiple-static scattering mitigates the effect of late-time onset on the robustness of the extracted resonance modes in the context of radar target classification. The assessment exploits the m...The paper assesses how multiple-static scattering mitigates the effect of late-time onset on the robustness of the extracted resonance modes in the context of radar target classification. The assessment exploits the mode distribution vs onset shift to verify the sensitivity of the mode’s extraction to the selected onset, especially higher-order, to onset. However, within some bistatic directions, the modes have enhanced energies with lesser specular energy, making the modes estimate less sensitive to onset shifts. Also, the mode distribution per bistatic and polarization configuration has demonstrated different onset windows of accurate and consistent mode extraction. Notably, the distribution of the mode energy distribution reveals that classification performance degrades with poorly selected onset.展开更多
The optical properties of AlGaN-based quantum well(QW)structure with two coupled thin well layers are investigated by the six-by-six K-P method.Compared with the conventional structure,the new structure,especially the...The optical properties of AlGaN-based quantum well(QW)structure with two coupled thin well layers are investigated by the six-by-six K-P method.Compared with the conventional structure,the new structure,especially the one with lower Al-content in the barrier layer,can enhance the TE-/TM-polarized total spontaneous emission rate due to the strong quantum confinement and wide recombination region.For the conventional QW structure,the reduction of well thickness can lead the degree of polarization(DOP)to decrease and the internal quantum efficiency(IQE)to increase.By using the coupled thin well layers,the DOP for the structure with high Al-content in the barrier layer can be improved,while the DOP will further decrease with low Al-content in the barrier layer.It can be attributed to the band adjustment induced by the combination of barrier height and well layer coupling.The IQE can also be further enhanced to 14.8%-20.5%for various Al-content of barrier layer at J=100 A/cm^(2).In addition,the efficiency droop effect can be expected to be suppressed compared with the conventional structure.展开更多
The high harmonic generation (HHG) from the CS<sub>2</sub> molecule in intense laser fields is investigated using the extended Lewenstein method. The initial state is the highest-occupied molecular orbital...The high harmonic generation (HHG) from the CS<sub>2</sub> molecule in intense laser fields is investigated using the extended Lewenstein method. The initial state is the highest-occupied molecular orbital of the CS<sub>2</sub> molecule, which can be well described by Gaussian wave packet using GAMESS-UK package. Compared with the case of the elliptical laser, the HHG can be extended in two-color circularly polarized laser field. The time-frequency analysis and classical electron trajectory as well as the ionization yield curve are also presented to further explain the underlying mechanism. After adding a static electric field on the z-direction, the single quantum path control is realized and the supercontinuum spectra are obtained. Moreover, an isolated 110 as pulse can be obtained by superposing the harmonics from 130th to 180th order.展开更多
The transfer function of the optical splitting system of the acousto-optic tunable filter (AOTF) is deduced to be a reference to optical design. The characteristic matrix (transfer function) of AOTF is used to des...The transfer function of the optical splitting system of the acousto-optic tunable filter (AOTF) is deduced to be a reference to optical design. The characteristic matrix (transfer function) of AOTF is used to describe quantitatively the characters of polarization elements in the orthogonal polarizing system. According to the characteristic matrix, the included angle of polarizer′s transmission direction and polarization analyzer′s transmission direction should be 90°. As a result the signal to noise ratio increased about 20 times though the light intensity was reduced to 54.300,because both the transmittances of polarizer and polarization analyzer are 0.74, which is an intrinsic character. The orthogonal polarizing method is an effective method to get rid of the influence of zero order light and improve the spectrum resolution and signal-to-noise ratio.展开更多
An improved measurement method of circularly-polarized (CP) antennas based on linear-component amplitudes is proposed in this paper. By utilizing two sets of orthogonal linear polarization (LP) amplitudes, measurement...An improved measurement method of circularly-polarized (CP) antennas based on linear-component amplitudes is proposed in this paper. By utilizing two sets of orthogonal linear polarization (LP) amplitudes, measurement on axial ratio (AR) of CP antennas can be realized without phase information. However, the rotation sense of the co-polarization cannot be determined due to the absence of the phase information. Above problem is discussed here for the first time, and a solution is presented to determine the rotation sense of the co-polarization by using common auxiliary CP antennas. In addition, there will be some particular cases with large errors in actual measurement. Here a corresponding solution method is given. Finally, co-polarization and cross-polarization patterns can be further obtained from AR results. To verify this improved method, a self-developed CP microstrip array was measured. The measured results are in agreement with the simulated results, which prove this method is correct, effective and practical.展开更多
针对光伏发电功率具有较强的波动性、间歇性输出,光伏功率预测精度较低,且难于给出具体预测时间长度等问题,提出了一种长相关随机模型分数阶布朗运动(fractional Brownian motion,FBM),用于光伏功率预测。首先,采用重标极差法计算长相关...针对光伏发电功率具有较强的波动性、间歇性输出,光伏功率预测精度较低,且难于给出具体预测时间长度等问题,提出了一种长相关随机模型分数阶布朗运动(fractional Brownian motion,FBM),用于光伏功率预测。首先,采用重标极差法计算长相关(long-range dependence,LRD)参数-Hurst指数,Hurst指数用于判断光伏功率数据是否满足长相关性,并通过最大李雅普诺夫指数(Lyapunov)计算出模型最大可预测时间尺度;其次,采用随机微分法建立FBM光伏功率预测模型,同时估计FBM预测模型参数值;最后,选取澳大利亚沙漠知识太阳能中心(Desert Knowledge Australia Solar Center,DKASC)、美国国家可再生能源实验室(National Renewable Energy Laboratory,NREL)以及北京国能日新科技有限公司的光伏功率数据集,从不同的地理环境、不同的气候特征、不同的规模大小电站进行验证。仿真结果表明,该模型较传统的Kalman、LSTM模型具有更高的预测精度,可为光伏并网的稳定和安全运行提供更好的理论支持,对电网调度部门具有较高的参考价值。展开更多
基金supported by the National Key Research and Development Program of China(2021YFA0715101)partly supported by a National LLR station project+2 种基金the National Natural Science Foundation of China(NSFC,Grant Nos.11973064 and 42101413)Jilin Province Mid-youth science and technology innovation and entrepreneurship outstanding talent project(20220508147RC)the Changchun City and Chinese Academy of Sciences Science and Technology Cooperation High-tech Industrialization Special Fund Project(21SH05)。
文摘Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes polarized.This study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the Moon.We obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the Moon.The findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria overall.Combining the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the Moon.This study may serve as a new diagnostic tool for the Moon.
文摘Metasurface-based polarimetry techniques have attracted lots of interests and been extensively studied in the past years,but are still hampered by narrow operating bandwidth and large crosstalk.Recently,Xian-Gang Luo's group proposed a new method of polarization-dependent phase optimization for the design of crosstalk-free,broadband achromatic,and full Stokes imaging polarimeter,which offers a promising platform for a wide range of applications including bio-photonics and integrated optics.
文摘A practical calibration method is proposed for instantaneous polarization radar systems.The method only needs one measurement by using a metal sphere.The distortions of system and the actual polarization scattering matrix(PSM)of target can be obtained.First,an instantaneous polarization radar system is presented.The system can obtain PSM by a single pulse echo.The dual-polarization antenna can transmit and receive two orthogonal polarization waves.The multilayer micro-strip patch antenna is adopted for this kind of radar system.Second,based on the multi-port network theory,the operation and system errors of instantaneous polarization radar system are analyzed.By making assumption on the cross-talk factors of antenna,distortion matrices of R and Tare derived.Finally,the calibration method based on instantaneous polarization measurement is introduced.Simulation results show the performance of this calibration method.The values of calibrated PSM are in agreement with the actual ones after calibration.
基金supported by the National Natural Science Foundation of China (Nos. 10732100, 10572155)the Science and Technology Planning Project of Guangdong Province of China (No. 2006A11001002)the Ph. D. Programs Foundation of Ministry of Education of China (No. 2006300004111179)
文摘Using a polarization method, the scattering problem for a two-dimensional inclusion embedded in infinite piezoelectric/piezomagnetic matrices is investigated. To achieve the purpose, the polarization method for a two-dimensional piezoelectric/piezomagnetic "comparison body" is formulated. For simple harmonic motion, kernel of the polarization method reduces to a 2-D time-harmonic Green's function, which is obtained using the Radon transform. The expression is further simplified under conditions of low frequency of the incident wave and small diameter of the inclusion. Some analytical expressions are obtained. The analytical solutions for generalized piezoelectric/piezomagnetic anisotropic composites are given followed by simplified results for piezoelectric composites. Based on the latter results, two numerical results are provided for an elliptical cylindrical inclusion in a PZT-5H-matrix, showing the effect of different factors including size, shape, material properties, and piezoelectricity on the scattering cross-section.
基金Guangdong Provincial Medical Science and Technology Research Fund Project(No.A2019507)Traditional Chinese Medicine Bureau of Guangdong Provincial Project(No.20191117)+1 种基金Science and Technology Program of Guangzhou(No.202102020927)National Administration of Traditional Chinese Medicine Clinical Research Base Business Construction Research Project(No.JDZX2015241)。
文摘Objective:To evaluate the effect of heat-clearing and detoxifying method on the macrophages polarization in patients with acute myocardial infarction with heat toxin syndrome after intervention.Methods:Sixty patients with acute myocardial infarction and undergoing percutaneous coronary intervention with heat toxin syndrome were randomly divided into a control group and a test group with 30 cases each.The control group was given conventional treatment,and the test group was given Huanglian Jiedu Decoction,the representative of the method of clearing heat and detoxification,orally on the basis of the control group.The intervention time of both groups was 2 weeks.Comparing The Seattle Angina Pectoris Scale(SAQ)before and after treatment,creatine kinase(CK),creatine kinase MB isoenzyme(CKMB),high-sensitivity troponin I(hs-TnI),and Lipoprotein-associated phospholipaseA2(LPPLA_2)),the phenotype ratio of M1 and M2 macrophages,and observe the adverse reactions.Results:After treatment,the SAQ scores of the two groups of patients were improved,and the levels of CK,CK-MB,hs-TnI,and LP-PLA_2 decreased significantly.The scores of AS,AF,TS,and DP in the SAQ of the test group were all higher than those of the control group,and the hs-TnI and LP-PLA_2 were better than those of the control Group(P<0.05 or P<0.01).After treatment,the proportion of M1 type macrophages in the two groups of patients'macrophages decreased significantly(P<0.05 or P<0.01),the ratio of M2 type macrophages increased(P<0.05),and the M1/M2 ratio decreased.The ratio of M1/M2 in the test group of the control group was significantly lower than that of the control group(P<0.01).There were no obvious adverse reactions in both groups.Conclusions:The method of clearing heat and detoxifying has a definite effect on patients with acute myocardial infarction of heat toxin syndrome after interventional operation.It can reduce myocardial damage,improve myocardial function,and reduce inflammation.And it is safe for clinical treatment without any increasing risk of bleeding or other risk of cardiovascular events.
基金supported by the Zhejiang Provincial Natural Science Foundation,China(Grant Nos.LZ17A040001 and LY16A040014)the National Natural Science Foundation of China(Grant Nos.11574271 and 11574272)+1 种基金the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministrythe Science Research Foundation of Zhejiang Sci-Tech University(ZSTU),China(Grant No.14062078-Y)
文摘The vectorial structure of an optical field with hybrid states of polarization (SOP) in the near-field is studied by using the angular spectrum method of an electromagnetic beam. Physical images of the longitudinal components of evanescent waves are illustrated and compared with those of the transverse components from the vectorial structure. Our results indicate that the relative weight integrated over the transverse plane of the evanescent wave depends strongly on the number of the polarization topological charges. The shapes of the intensity profiles of the longitudinal components are different from those of the transverse components, and it can be manipulated by changing the initial SoP of the field cross-section. The longitudinal component of evanescent wave dominates the near-field region. In addition, it also leads to three-dimensional shape variations of the optical field and the optical spin angular momentum flux density distributions.
文摘A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous Hamiltonian system is multiplied by a set of multiplicative functions, then the general expression of the first integral can be obtained, An example is given to illustrate the application of the results.
文摘A novel matching method for simultaneous multi-target recognition is proposed by jointly considering target's prior scattering knowledge and the polarization parameters of radar echoes. The matching coefficients are calculated for the judgment. MATLAB simulations show that several targets can be accurately recognized simultaneously, and a high recognition probability can be achieved in Monte Carlo simulations. The total execution time can be remarkably reduced in the Field Programmable Gate Array (FPGA) implementation of the matching procedure.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11274181,10974100,61203204,and 10674075)the Doctoral Scientific Fund Project of the Ministry of Education of China(Grant No.20120031110033)the Tianjin Key Program of Application Foundations and Future Technology Research Project,China(Grant No.10JCZDJC24300)
文摘A new polarization rotator based on the silica photonic crystal fiber is proposed. The proposed polarization rotator photonic crystal fiber (PR-PCF) possesses a triangle jigsaw-shape core region. The full-vector finite-element method is used to analyze the phenomenon of polarization conversion between the quasi-TE and quasi-TM modes. Numerical simulations show that the wavelengths of 1.31 μm and 1.55 μm are converted with a nearly 100% polarization conversion ratio with their matched coupling length and has a relatively strong realistic fabrication tolerance - 100 nm on the y axis and 50 nm on the x axis. The full vectorial finite difference beam propagation method is used to confirm the performance of the proposed PR-PCF.
文摘Using discrete variational X. method within the local-density-functional theory and cluster models, the electronic structure and magnetic property or MnSh(Ce) are investigated.It is round that Sb5p state is much polarized by Ce doping.The spin moment of Sb changes from -0.06 V,in MnSh to -0.32μb, in MnSh(Ce).The interaction between Mn and doped Ce is small compared with that between Sb and Ce in MnSh(Ce).The influence to the magneto-optical Property of MnSh by the doped Ce is discussed. It is expected that the Sb-5p polarization caused by Ce will make MnSh(Ce)a promising magneto-optical material.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11274254,91126007 and 11264033.
文摘Detailed calculations are carried out for the electron-impact excitation cross sections from the ground state to the individual magnetic sublevels of the 1s2s^(2)2p^(3)/2 J=2 excited state of highly-charged beryllium-like ions by using a fully relativistic distorted-wave(RDW)method.The contributions of the Breit interaction to the linear polarization of the 1s2s^(2)2p^(3)/2 J=2→1s22s2 J=0 magnetic quadrupole(M2)line are investigated systematically for the beryllium isoelectronic sequence with 42≤Z≤92.It is found that the Breit interaction depolarizes significantly the linear polarization of the M2 fluorescence radiation and that these depolarization effects increase as the incident electron energy and/or the atomic number is enlarged.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11264021 and 11074069the Youth Science Foundation of Jiangxi Province under Grant Nos 20114BAB212001 and 20132BAB216011.
文摘We numerically demonstrate the modulation of plasmon resonances in a metamolecule composed of metal bars and L-shaped nanoparticles by using the finite difference time domain method.Due to the dependence of electromagnetic coupling on polarization of the incident light,we show that the superradiant and subradiant states can be switched from ON and OFF resonantly.These two resonances are continuously adjustable as the polarization angle of incident wave changes.This feature reveals a possibility of dynamically switching the coupled plasmon resonances of an artificial microstructure and to construct functional metamaterials,which is helpful for nanophotonic devices such as filters and optical switches.
文摘The paper assesses how multiple-static scattering mitigates the effect of late-time onset on the robustness of the extracted resonance modes in the context of radar target classification. The assessment exploits the mode distribution vs onset shift to verify the sensitivity of the mode’s extraction to the selected onset, especially higher-order, to onset. However, within some bistatic directions, the modes have enhanced energies with lesser specular energy, making the modes estimate less sensitive to onset shifts. Also, the mode distribution per bistatic and polarization configuration has demonstrated different onset windows of accurate and consistent mode extraction. Notably, the distribution of the mode energy distribution reveals that classification performance degrades with poorly selected onset.
基金Project supported by the National Natural Science Foundation of China(Grant No.61874168)the Jiangsu Province I-U-R Cooperation Project,China(Grant No.BY2019114)the Nantong Science and Technology Project,China(Grant No.JC2019006)。
文摘The optical properties of AlGaN-based quantum well(QW)structure with two coupled thin well layers are investigated by the six-by-six K-P method.Compared with the conventional structure,the new structure,especially the one with lower Al-content in the barrier layer,can enhance the TE-/TM-polarized total spontaneous emission rate due to the strong quantum confinement and wide recombination region.For the conventional QW structure,the reduction of well thickness can lead the degree of polarization(DOP)to decrease and the internal quantum efficiency(IQE)to increase.By using the coupled thin well layers,the DOP for the structure with high Al-content in the barrier layer can be improved,while the DOP will further decrease with low Al-content in the barrier layer.It can be attributed to the band adjustment induced by the combination of barrier height and well layer coupling.The IQE can also be further enhanced to 14.8%-20.5%for various Al-content of barrier layer at J=100 A/cm^(2).In addition,the efficiency droop effect can be expected to be suppressed compared with the conventional structure.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11574117,11271158,61575077 and 11575071
文摘The high harmonic generation (HHG) from the CS<sub>2</sub> molecule in intense laser fields is investigated using the extended Lewenstein method. The initial state is the highest-occupied molecular orbital of the CS<sub>2</sub> molecule, which can be well described by Gaussian wave packet using GAMESS-UK package. Compared with the case of the elliptical laser, the HHG can be extended in two-color circularly polarized laser field. The time-frequency analysis and classical electron trajectory as well as the ionization yield curve are also presented to further explain the underlying mechanism. After adding a static electric field on the z-direction, the single quantum path control is realized and the supercontinuum spectra are obtained. Moreover, an isolated 110 as pulse can be obtained by superposing the harmonics from 130th to 180th order.
文摘The transfer function of the optical splitting system of the acousto-optic tunable filter (AOTF) is deduced to be a reference to optical design. The characteristic matrix (transfer function) of AOTF is used to describe quantitatively the characters of polarization elements in the orthogonal polarizing system. According to the characteristic matrix, the included angle of polarizer′s transmission direction and polarization analyzer′s transmission direction should be 90°. As a result the signal to noise ratio increased about 20 times though the light intensity was reduced to 54.300,because both the transmittances of polarizer and polarization analyzer are 0.74, which is an intrinsic character. The orthogonal polarizing method is an effective method to get rid of the influence of zero order light and improve the spectrum resolution and signal-to-noise ratio.
文摘An improved measurement method of circularly-polarized (CP) antennas based on linear-component amplitudes is proposed in this paper. By utilizing two sets of orthogonal linear polarization (LP) amplitudes, measurement on axial ratio (AR) of CP antennas can be realized without phase information. However, the rotation sense of the co-polarization cannot be determined due to the absence of the phase information. Above problem is discussed here for the first time, and a solution is presented to determine the rotation sense of the co-polarization by using common auxiliary CP antennas. In addition, there will be some particular cases with large errors in actual measurement. Here a corresponding solution method is given. Finally, co-polarization and cross-polarization patterns can be further obtained from AR results. To verify this improved method, a self-developed CP microstrip array was measured. The measured results are in agreement with the simulated results, which prove this method is correct, effective and practical.
文摘针对光伏发电功率具有较强的波动性、间歇性输出,光伏功率预测精度较低,且难于给出具体预测时间长度等问题,提出了一种长相关随机模型分数阶布朗运动(fractional Brownian motion,FBM),用于光伏功率预测。首先,采用重标极差法计算长相关(long-range dependence,LRD)参数-Hurst指数,Hurst指数用于判断光伏功率数据是否满足长相关性,并通过最大李雅普诺夫指数(Lyapunov)计算出模型最大可预测时间尺度;其次,采用随机微分法建立FBM光伏功率预测模型,同时估计FBM预测模型参数值;最后,选取澳大利亚沙漠知识太阳能中心(Desert Knowledge Australia Solar Center,DKASC)、美国国家可再生能源实验室(National Renewable Energy Laboratory,NREL)以及北京国能日新科技有限公司的光伏功率数据集,从不同的地理环境、不同的气候特征、不同的规模大小电站进行验证。仿真结果表明,该模型较传统的Kalman、LSTM模型具有更高的预测精度,可为光伏并网的稳定和安全运行提供更好的理论支持,对电网调度部门具有较高的参考价值。