By employing a full quantum theory of electron-photon scattering in intense laser fields,we calculate the angularresolved radiation rate of the fundamental wave in Thomson scattering.We investigate the dependence of r...By employing a full quantum theory of electron-photon scattering in intense laser fields,we calculate the angularresolved radiation rate of the fundamental wave in Thomson scattering.We investigate the dependence of radiation rate on Euler angles and elucidate the underlying physical mechanism.The figure-8 profile of the radiation rate within the polarization plane is validated,while its evolution with respect to laser intensity and electron momentum is illustrated.Our findings reveal that in lower-intensity laser fields and for slow electron motion,the angular-resolved radiation rate exhibits distinct dipole emission characteristics.However,significant changes are observed at high laser intensities and/or large electron momenta,leading to pronounced alterations in the angular-resolved radiation rate.Remarkably similar variation patterns can be achieved by proportionally adjusting both laser intensity and electron momentum.展开更多
Imaging scenes with a high dynamic range(HDR)of light intensities is critical for applications such as biomedical imaging,astronomical observation,and industrial automation,where accurate detection of both bright and ...Imaging scenes with a high dynamic range(HDR)of light intensities is critical for applications such as biomedical imaging,astronomical observation,and industrial automation,where accurate detection of both bright and dark regions is essential for precise analysis and decision-making.In this paper,we propose an HDR imaging approach harnessing optical forward scattering effect that breaks the limitations of image processing type.Our approach integrates a nonlinear deconvolution method based on speckle background noise estimation,along with Cross-correlation and Laplacian pyramid fusion method,to improve imaging precision and adaptability.By utilizing a digital micromirror device and a scattering diffuser,we develop a proof-of-concept experimental system,validating the effectiveness of reconstruction of faint details in HDR scenes.This method achieves dynamic range expansion from a 130.01 dB HDR scene using a detector with an 88.5 dB dynamic range,achieving a 119-fold intensity difference.Our work demonstrates a promising new solution for HDR imaging in demanding lighting environments,which could expand the scope of photoelectronic imaging application.展开更多
Known as a weak topological insulator(TI),BiSe structurally exhibits alternating stacks of quantum spin Hall bilayer("Bi_(2)")and three-dimensional TI layer("Bi_(2)Se_(3)").The low lattice thermal ...Known as a weak topological insulator(TI),BiSe structurally exhibits alternating stacks of quantum spin Hall bilayer("Bi_(2)")and three-dimensional TI layer("Bi_(2)Se_(3)").The low lattice thermal conductivity of BiSe due to the presence of Bi2 bilayers promises potentially good thermoelectric performance.Herein,the thermoelectric properties of nominal Bi_(1-x)Cu_(x)Se samples were studied as the functions of the content of Cu additive and temperature.It is found that Cu additives in BiSe(1)profoundly affect the texture of densified polycrystalline samples by inclining the crystallographic c-axis parallel toward the pressure direction in the densification process,(2)increase considerably the effective mass and thus the Seebeck coefficient,and(3)yield point defects and Cu-Se secondary phases that effectively scatter heat-carrying phonons.As a result,the optimized electrical and thermal properties yield a thermoelectric figure of merit of zT~0.29 in Bi_(1-x)Cu_(x)Se(x=0.03)sample at 467 K in parallel to the pressure direction and a zT~0.20 at 468 K in the perpendicular direction.展开更多
Propertiss of damping electrons in collision with photons based onmulti- photon nonlinear Compton effect are investigated. Theexpressions of the differential scattering section are derived.Several useful conclusions a...Propertiss of damping electrons in collision with photons based onmulti- photon nonlinear Compton effect are investigated. Theexpressions of the differential scattering section are derived.Several useful conclusions are drawn.展开更多
In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogde...In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogden and Erskine＇s experiments, sound scattering from the sea surface has three different regimes in which two mechanisms of surface roughness and subsurface bubble clouds are involved. Ogden-Erskine＇s scattering relation which consists of perturbation theory and Chapman-Harris＇s scattering terms are verified by the experimental data of Critical Sea Tests 7. Subsequently, wind speed in the Persian Gulf is provided based on three data bases of Arzanah station, ERA40, and PERGOS. Accordingly, surface scattering strength in the Persian Gulf region is calculated at different grazing angles, frequencies and provided wind speeds. Based on the resulted values of scattering strength, scattered intensity from the sea surface is also studied. These studies indicate that both scattering strength and scattered intensity generally increase as grazing angle, frequency and wind speed increase.展开更多
As the feature size of the CMOS integrated circuit continues to shrink, the more and more serious scattering effect has a serious impact on interconnection performance, such as delay and bandwidth. Based on the impact...As the feature size of the CMOS integrated circuit continues to shrink, the more and more serious scattering effect has a serious impact on interconnection performance, such as delay and bandwidth. Based on the impact of the scattering effect on latency and bandwidth, this paper first presents the quality-factor model which optimises latency and bandwidth effectively with the consideration of the scattering effect. Then we obtain the analytical model of line width and spacing with application of curve-fitting method. The proposed model has been verified and compared based on the nano-scale CMOS technology. This optimisation model algorithm is simple and can be applied to the interconnection system optimal design of nano-scale integrated circuits.展开更多
We investigate the effects of dynamical Casimir effect in superradiant light scattering by Bose-Einstein condensate in an optomechanical cavity. The system is studied using both classical and quantized mirror motions....We investigate the effects of dynamical Casimir effect in superradiant light scattering by Bose-Einstein condensate in an optomechanical cavity. The system is studied using both classical and quantized mirror motions. The cavity frequency is harmonically modulated in time for both the cases. The main quantity of interest is the number of intracavity scattered photons. The system has been investigated under the weak and strong modulations. It has been observed that the amplitude of the scattered photons is more for the classical mirror motion than the quantized mirror motion. Also, initially, the amplitude of scattered photons is high for lower modulation amplitude than higher modulation amplitude. We also found that the behavior of the plots are similar under strong and weak modulations for the quantized mirror motion.展开更多
The effect of solvent on surface enhanced Raman scattering [SERS) of colloidal silver has been studied. Experiments show that the intensity of SERS is related to the polarity and molecular constitution of the solvent....The effect of solvent on surface enhanced Raman scattering [SERS) of colloidal silver has been studied. Experiments show that the intensity of SERS is related to the polarity and molecular constitution of the solvent. The influence of solvent is due to the change of the adsorption quantity and adsorption intensity.展开更多
The conversion efficiency of stimulated Raman scattering （SRS） in CH4 is studied by using a single longitudinal mode second-harmonic Nd：YAG laser （532 nm, linewidth 0.003 cm^-1, pulse-width （FWHM） 6.5 ns）. Due ...The conversion efficiency of stimulated Raman scattering （SRS） in CH4 is studied by using a single longitudinal mode second-harmonic Nd：YAG laser （532 nm, linewidth 0.003 cm^-1, pulse-width （FWHM） 6.5 ns）. Due to the heat release from vibrationally excited particles, SRS processes often suffer from the thermal defocusing effect （TDE）. In view of 6.5 ns laser pulse width is much shorter than the vibrational relaxation time of CH4 molecules, TDE can only affect the SRS processes afterwards. In the cases of low laser repetition, TDE will be not serious, because it will be removed by the thermal diffusion in Raman medium before the next pulse arrives. At the laser repetition rate 2 Hz, CH4 pressure 1.1 MPa and pump laser energy 95 mJ, the quantum conversion efficiency of backward first-Stokes （BS1） has attained 73%. This represents the highest first-stokes conversion efficiency in CH4. Furthermore, due to the relaxation oscillation, the BS1 pulses are narrowed to about 1.2 ns. As a result, the BS1 peak power turns out to be 2.7 times that of the pump. Its beam quality is also much better and is only slightly affected by TDE. This reason is that BS1 represents a wave-front-reversed replica of the pump beam, which can compensate the thermal distortions in Raman amplify process. Under the same conditions, but pump laser repetition rate as 10 Hz, the conversion efficiency of BS1 goes down to 36% due to TDE. From this study, we expect that a well-behaved 630 nm Raman laser may be designed by using a closed CH4/He circulating-cooling system, which may have some important applications.展开更多
This study investigates the mechanism of ^(6)Li+^(7)Li anomalous large-angle scattering.First,elastic scattering is analyzed using an optical model with the São Paulo potential,and inelastic scattering to the fir...This study investigates the mechanism of ^(6)Li+^(7)Li anomalous large-angle scattering.First,elastic scattering is analyzed using an optical model with the São Paulo potential,and inelastic scattering to the first excited state of ^(7)Li is analyzed by distorted wave born approximation method.The experimental data of the elastic scattering angular distributions could be described reasonably well by the optical model at forward angles;however,anomalous large-angle scattering is observed in the angular distributions of both the elastic and inelastic channels for all measured energies.Elastic and inelastic scatterings are investigated using the coupled reaction channel method.The elastic and inelastic scattering,transfer reactions for the ground and excited states,and their coupling effects are considered in the coupled reaction channel scheme.In addition,the influence of the breakup effects of the weakly bound ^(6)Li and ^(7)Li is investigated by including three resonance states of ^(6)Li and two resonance states of ^(7)Li in the coupled reaction channel framework.The observed anomalous large-angle scattering is explained using the transfer reaction mechanism and breakup effect,and the calculated results reproduce the experimental data reasonably well.展开更多
Information concerns endocytosis and autophagic effects of magnetite particles is crucial for understanding the particle-cell interactions. In this work, we investigated the effects of bovine serum proteins on the end...Information concerns endocytosis and autophagic effects of magnetite particles is crucial for understanding the particle-cell interactions. In this work, we investigated the effects of bovine serum proteins on the endocytosis of magnetite spherical particles（MSPs）. Autophagic effects of MSPs in breast cancer cells were studied. Light scattering based flow cytometry and microscopy were used for evaluating the uptake potential of MSPs by cells and the cellular autophagosome accumulation. Results showed bovine serum proteins significantly reduced the endocytosis of MSPs by decreasing their adsorption to cell membranes. Additionally, serum proteins had influences on the endocytic mechanisms of MSPs.Autophagosome accumulation could be caused by the internalized MSPs rather than the particles associated with cell membrane. Above fundamental findings promote our understandings upon the interactions of MSPs with cells. Light scattering based methods were proved to be simple and effective.The present work may promote their application in studies upon endocytosis of metallic particles in the future.展开更多
High performance optical diode-like devices are highly desired in future practical nano-photonic devices with strong directional selectivity.We demonstrate a kind of giant broadband reciprocity optical diode-like devi...High performance optical diode-like devices are highly desired in future practical nano-photonic devices with strong directional selectivity.We demonstrate a kind of giant broadband reciprocity optical diode-like devices by simultaneously using the directional Mie scattering effect and the asymmetric grating diffraction effect.The maximum asymmetric subtraction and the asymmetric transmission ratio can reach nearly 100%and 40dB at specified wavelength,respectively.In a wide waveband from 500nm to 800nm,the asymmetric subtraction and the ratio keep larger than 80%and 3.5 dB,respectively,even under oblique incidence.To the best of our knowledge,this is the best one-way-transmission effect observed in the reciprocity optical diode-like devices.In addition,we further demonstrate that this one-way-transmission effect can bring an effective absorption enhancement on gold films.The giant,broadband and angle-insensitive one-way-transmission effect demonstrated here is far beyond the well-known anti-reflection effect in the light-trapping devices and will bring new design philosophy for nano-photonic devices.展开更多
A state diagnosis of laser-produced plasma in air generated by a 1064 nm pulse laser was investigated by the Thomson scattering(TS)method.The evolutions of the electron temperature and electron density were obtained a...A state diagnosis of laser-produced plasma in air generated by a 1064 nm pulse laser was investigated by the Thomson scattering(TS)method.The evolutions of the electron temperature and electron density were obtained as a function of the time delay which ranged from 300-3200 ns.The heating effect produced by the 532 nm probe beam with different energies on the air plasma at different interaction times was further studied using a time-resolved optical emission spectroscopy technique.The influence of the probe beam on the electron density was found to be negligible,whereas its influence on electron temperature is evident.In addition,the heating effect of the probe beam on the plasma strongly depends on the energy of the probe beam,and gradually weakens with increasing time delay.Our results are helpful for further understanding the TS method and its application in plasma diagnostics.展开更多
Calculation of the scattered field of the eccentric scatterers is an old problem with numerous applications. This study considers the interaction of a plane compressional sound wave with a liquid-encapsulated thermovi...Calculation of the scattered field of the eccentric scatterers is an old problem with numerous applications. This study considers the interaction of a plane compressional sound wave with a liquid-encapsulated thermoviscous fluid cylinder submerged in an unbounded viscous thermally conducting medium. The translational addition theorem for cylindrical wave functions, the appropriate wave field expansions and the pertinent boundary conditions are employed to develop a closed-form solution in the form of infinite series. The analytical results are illustrated with a numerical example in which the compound cylinder is insonified by a plane sound wave at selected angles of incidence in a wide range of dimensionless frequencies. The backscattered far-field acoustic pressure amplitude and the spatial distribution of the total acoustic pressure in the vicinity of the cylinder are evaluated and discussed for representative values of the parameters characterizing the system. The effects of incident wave frequency, angle of incidence, fluid thermoviscosity, core eccentricity and size are thoroughly examined. Limiting case involving an ideal com- pressible liquid-coated cylinder is considered and fair agreement with a well-known solution is established.展开更多
The K<SUP>+</SUP> scattering cross section with the in-medium virtual pion is evaluated in the lowest-order chiral perturbation theory with the density-dependent pion decay constant and mass. The contribut...The K<SUP>+</SUP> scattering cross section with the in-medium virtual pion is evaluated in the lowest-order chiral perturbation theory with the density-dependent pion decay constant and mass. The contribution of nuclear pions to the total K<SUP>+</SUP>-nucleus cross section is found to be about 5% and 12% when the excess pion numbers per nucleon n<SUB>?</SUB> = 0.057 and 0.13 are used. The inclusion of the off-mass-shell behavior of the K<SUP>+</SUP>? amplitude produced a significant improvement in the K<SUP>+</SUP>-nucleus cross section.展开更多
The rate of hydrothermal reaction of SiO_2 and/or A1_2O_3 in the system of CaO-Al_2O_3-SiO_2-H_2O at 200℃ and the factors which influence the reactions are investigated by determining the reaction ratio.The rate of r...The rate of hydrothermal reaction of SiO_2 and/or A1_2O_3 in the system of CaO-Al_2O_3-SiO_2-H_2O at 200℃ and the factors which influence the reactions are investigated by determining the reaction ratio.The rate of reactions depends on the reactive activities of raw materials, initial composition of mixture and relative activity of SiO_2 and A12O3. The hydrothermal reaction can be accelerated by sodium hydroxide,in the case of silica,which has low activity, this is quite obvious.展开更多
A new Monte Carlo simulation of the track structure of low-energy electrons （〈10keV） in liquid water is presented. The feature of the simulation is taken into consideration of the condensed-phase effect of liquid w...A new Monte Carlo simulation of the track structure of low-energy electrons （〈10keV） in liquid water is presented. The feature of the simulation is taken into consideration of the condensed-phase effect of liquid water on electron elastic scattering with the use of the Champion model, while the dielectric response formalism incorporating the optical-data model developed by Emfietzoglou et al. is applied for calculating the electron inelastic scattering. The spatial distributions of energy deposition and inelastic scattering events of low-energy electrons with different primary energies in liquid water are calculated and compared with other theoretical evaluations. The present work shows that the condensed-phase effect of liquid water on electron elastic scattering may be of the influence on the fraction of absorbed energy and distribution of inelastic scattering events at lower primary energies, which also indicate potential effects on the DNA damage induced by low-energy electrons.展开更多
The magnetic properties and Kondo effect in Ce_(3)TiBi_(5) with a quasi-one-dimensional structure were investigated using in situ high-pressure resistivity measurements up to 48 GPa.At ambient pressure,Ce_(3)TiBi_(5) ...The magnetic properties and Kondo effect in Ce_(3)TiBi_(5) with a quasi-one-dimensional structure were investigated using in situ high-pressure resistivity measurements up to 48 GPa.At ambient pressure,Ce_(3)TiBi_(5) undergoes an antiferromagnetic(AFM)transition at T_(N)∼5 K.Under high pressures within 8.9 GPa,we find that Kondo scattering contributes differently to the high-temperature resistance,R(T),depending on the applied current direction,demonstrating a significantly anisotropic Kondo effect.The complete P–T phase diagram has been constructed,in which the pressure dependence of T_(N) exhibits a dome-like shape.The AFM order remains robust under pressure,even when the coherence temperature T^(*) far exceeds 300 K.We attribute the observed anisotropic Kondo effect and the robust AFM to the underlying anisotropy in electronic hybridization under high pressure.展开更多
The results of comprehensive microscopic optical model calculations are pres-ented for the K<sup>+</sup> scattering from <sup>6</sup>Li,<sup>12</sup>C,<sup>28</sup>Si an...The results of comprehensive microscopic optical model calculations are pres-ented for the K<sup>+</sup> scattering from <sup>6</sup>Li,<sup>12</sup>C,<sup>28</sup>Si and <sup>40</sup>Ca at incident momenta 400-800MeV/c.The unconventional medium effect （i.e.the density-dependent correction forthe K<sup>+</sup>-nucleon scattering amplitude） is considered in two approaches.Both results arein agreement with recent experimental data.The influence of the correction on K<sup>+</sup> scat-tering from different nuclei are discussed in detail and only a weak dependence of thein-medium nucleon“swelling”effects on the mass number of target nuclei is found ex-cept for very light loosely-bound nucleus.展开更多
By making use of the quasi-two-dimensional （quasi-2D） model, the current-voltage （l-V） characteristics of In0AsA10.82N/A1N/GaN heterostructure field-effect transistors （HFETs） with different gate lengths are sim...By making use of the quasi-two-dimensional （quasi-2D） model, the current-voltage （l-V） characteristics of In0AsA10.82N/A1N/GaN heterostructure field-effect transistors （HFETs） with different gate lengths are simulated based on the measured capacitance-voltage （C-V） characteristics and I-V characteristics. By analyzing the variation of the electron mobility for the two-dimensional electron gas （2DEG） with electric field, it is found that the different polarization charge distributions generated by the different channel electric field distributions can result in different polarization Coulomb field scatterings. The difference between the electron mobilities primarily caused by the polarization Coulomb field scatterings can reach up to 1522.9 cm2/V.s for the prepared In0.38AI0.82N/A1N/GaN HFETs. In addition, when the 2DEG sheet density is modulated by the drain-source bias, the electron mobility presents a peak with the variation of the 2DEG sheet density, the gate length is smaller, and the 2DEG sheet density corresponding to the peak point is higher.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12074261)the Natural Science Foundation of Shanghai(Grant No.20ZR1441600)。
文摘By employing a full quantum theory of electron-photon scattering in intense laser fields,we calculate the angularresolved radiation rate of the fundamental wave in Thomson scattering.We investigate the dependence of radiation rate on Euler angles and elucidate the underlying physical mechanism.The figure-8 profile of the radiation rate within the polarization plane is validated,while its evolution with respect to laser intensity and electron momentum is illustrated.Our findings reveal that in lower-intensity laser fields and for slow electron motion,the angular-resolved radiation rate exhibits distinct dipole emission characteristics.However,significant changes are observed at high laser intensities and/or large electron momenta,leading to pronounced alterations in the angular-resolved radiation rate.Remarkably similar variation patterns can be achieved by proportionally adjusting both laser intensity and electron momentum.
基金supported by National Natural Science Foundation of China(NSFC)(62105254,62205259,62375212,and 62405231)Fundamental Research Funds for the Central Universities(XJSJ24028,XJS222202,and YJSJ25010)+1 种基金Science Fund for Distinguished Young Scholars of Shaanxi Province(2024JC-JCQN-60)National Key Laboratory of Space Target Awareness,and Innovation Fund of Xidian University.
文摘Imaging scenes with a high dynamic range(HDR)of light intensities is critical for applications such as biomedical imaging,astronomical observation,and industrial automation,where accurate detection of both bright and dark regions is essential for precise analysis and decision-making.In this paper,we propose an HDR imaging approach harnessing optical forward scattering effect that breaks the limitations of image processing type.Our approach integrates a nonlinear deconvolution method based on speckle background noise estimation,along with Cross-correlation and Laplacian pyramid fusion method,to improve imaging precision and adaptability.By utilizing a digital micromirror device and a scattering diffuser,we develop a proof-of-concept experimental system,validating the effectiveness of reconstruction of faint details in HDR scenes.This method achieves dynamic range expansion from a 130.01 dB HDR scene using a detector with an 88.5 dB dynamic range,achieving a 119-fold intensity difference.Our work demonstrates a promising new solution for HDR imaging in demanding lighting environments,which could expand the scope of photoelectronic imaging application.
基金the Graduate Scientific Research and Innovation Foundation of Chongqing,China(No.CYB 19064)the National Natural Science Foundation of China(Nos.51772035,11674040,51472036 and 51672270)+4 种基金the Fundamental Research Funds for the Central Universities(No.106112017CDJQJ308821)the Key Research Program of Frontier Sciences,CAS(No.QYZDB-SSW-SLH016)the CSC Scholarship(No.201806050180)2019 ITS Summer Fellowship,the Natural Science Foundation of Chongqing,China(No.cstc2019jcyj-msxmX0554)the Starting Research Fund from Chongqing University。
文摘Known as a weak topological insulator(TI),BiSe structurally exhibits alternating stacks of quantum spin Hall bilayer("Bi_(2)")and three-dimensional TI layer("Bi_(2)Se_(3)").The low lattice thermal conductivity of BiSe due to the presence of Bi2 bilayers promises potentially good thermoelectric performance.Herein,the thermoelectric properties of nominal Bi_(1-x)Cu_(x)Se samples were studied as the functions of the content of Cu additive and temperature.It is found that Cu additives in BiSe(1)profoundly affect the texture of densified polycrystalline samples by inclining the crystallographic c-axis parallel toward the pressure direction in the densification process,(2)increase considerably the effective mass and thus the Seebeck coefficient,and(3)yield point defects and Cu-Se secondary phases that effectively scatter heat-carrying phonons.As a result,the optimized electrical and thermal properties yield a thermoelectric figure of merit of zT~0.29 in Bi_(1-x)Cu_(x)Se(x=0.03)sample at 467 K in parallel to the pressure direction and a zT~0.20 at 468 K in the perpendicular direction.
文摘Propertiss of damping electrons in collision with photons based onmulti- photon nonlinear Compton effect are investigated. Theexpressions of the differential scattering section are derived.Several useful conclusions are drawn.
文摘In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogden and Erskine＇s experiments, sound scattering from the sea surface has three different regimes in which two mechanisms of surface roughness and subsurface bubble clouds are involved. Ogden-Erskine＇s scattering relation which consists of perturbation theory and Chapman-Harris＇s scattering terms are verified by the experimental data of Critical Sea Tests 7. Subsequently, wind speed in the Persian Gulf is provided based on three data bases of Arzanah station, ERA40, and PERGOS. Accordingly, surface scattering strength in the Persian Gulf region is calculated at different grazing angles, frequencies and provided wind speeds. Based on the resulted values of scattering strength, scattered intensity from the sea surface is also studied. These studies indicate that both scattering strength and scattered intensity generally increase as grazing angle, frequency and wind speed increase.
基金supported by the National Natural Science Foundation of China (Grant Nos.60725415 and 60971066)the National High-tech Program (Grant Nos.2009AA01Z258 and 2009AA01Z260)the National Key Lab Foundation (Grant No.ZHD200904)
文摘As the feature size of the CMOS integrated circuit continues to shrink, the more and more serious scattering effect has a serious impact on interconnection performance, such as delay and bandwidth. Based on the impact of the scattering effect on latency and bandwidth, this paper first presents the quality-factor model which optimises latency and bandwidth effectively with the consideration of the scattering effect. Then we obtain the analytical model of line width and spacing with application of curve-fitting method. The proposed model has been verified and compared based on the nano-scale CMOS technology. This optimisation model algorithm is simple and can be applied to the interconnection system optimal design of nano-scale integrated circuits.
文摘We investigate the effects of dynamical Casimir effect in superradiant light scattering by Bose-Einstein condensate in an optomechanical cavity. The system is studied using both classical and quantized mirror motions. The cavity frequency is harmonically modulated in time for both the cases. The main quantity of interest is the number of intracavity scattered photons. The system has been investigated under the weak and strong modulations. It has been observed that the amplitude of the scattered photons is more for the classical mirror motion than the quantized mirror motion. Also, initially, the amplitude of scattered photons is high for lower modulation amplitude than higher modulation amplitude. We also found that the behavior of the plots are similar under strong and weak modulations for the quantized mirror motion.
文摘The effect of solvent on surface enhanced Raman scattering [SERS) of colloidal silver has been studied. Experiments show that the intensity of SERS is related to the polarity and molecular constitution of the solvent. The influence of solvent is due to the change of the adsorption quantity and adsorption intensity.
文摘The conversion efficiency of stimulated Raman scattering （SRS） in CH4 is studied by using a single longitudinal mode second-harmonic Nd：YAG laser （532 nm, linewidth 0.003 cm^-1, pulse-width （FWHM） 6.5 ns）. Due to the heat release from vibrationally excited particles, SRS processes often suffer from the thermal defocusing effect （TDE）. In view of 6.5 ns laser pulse width is much shorter than the vibrational relaxation time of CH4 molecules, TDE can only affect the SRS processes afterwards. In the cases of low laser repetition, TDE will be not serious, because it will be removed by the thermal diffusion in Raman medium before the next pulse arrives. At the laser repetition rate 2 Hz, CH4 pressure 1.1 MPa and pump laser energy 95 mJ, the quantum conversion efficiency of backward first-Stokes （BS1） has attained 73%. This represents the highest first-stokes conversion efficiency in CH4. Furthermore, due to the relaxation oscillation, the BS1 pulses are narrowed to about 1.2 ns. As a result, the BS1 peak power turns out to be 2.7 times that of the pump. Its beam quality is also much better and is only slightly affected by TDE. This reason is that BS1 represents a wave-front-reversed replica of the pump beam, which can compensate the thermal distortions in Raman amplify process. Under the same conditions, but pump laser repetition rate as 10 Hz, the conversion efficiency of BS1 goes down to 36% due to TDE. From this study, we expect that a well-behaved 630 nm Raman laser may be designed by using a closed CH4/He circulating-cooling system, which may have some important applications.
基金supported by the President’s Fund of China Academy of Engineering Physics(No.YZJJZQ2023022)Nature Science Foundation of Shanxi Province,China(Nos.202103021224309 and 201901D111317).
文摘This study investigates the mechanism of ^(6)Li+^(7)Li anomalous large-angle scattering.First,elastic scattering is analyzed using an optical model with the São Paulo potential,and inelastic scattering to the first excited state of ^(7)Li is analyzed by distorted wave born approximation method.The experimental data of the elastic scattering angular distributions could be described reasonably well by the optical model at forward angles;however,anomalous large-angle scattering is observed in the angular distributions of both the elastic and inelastic channels for all measured energies.Elastic and inelastic scatterings are investigated using the coupled reaction channel method.The elastic and inelastic scattering,transfer reactions for the ground and excited states,and their coupling effects are considered in the coupled reaction channel scheme.In addition,the influence of the breakup effects of the weakly bound ^(6)Li and ^(7)Li is investigated by including three resonance states of ^(6)Li and two resonance states of ^(7)Li in the coupled reaction channel framework.The observed anomalous large-angle scattering is explained using the transfer reaction mechanism and breakup effect,and the calculated results reproduce the experimental data reasonably well.
基金the support from the University of MichiganThe National Natural Science Foundation of China (Nos. 61527806)+4 种基金National Key Research and Development Program of China (No. 2017YFA0205301)Natural Science Foundation of jiangsu Province(No. BK20141397)National Key Program for Developing Basic Research(No. 2014CB744501)Research Fund for the Doctoral Program of Higher Education of China(No.20120092120042)CMA-L'Oreal China Skin Grant 2015 (No. S2015121421) are also acknowledged for the financial support
文摘Information concerns endocytosis and autophagic effects of magnetite particles is crucial for understanding the particle-cell interactions. In this work, we investigated the effects of bovine serum proteins on the endocytosis of magnetite spherical particles（MSPs）. Autophagic effects of MSPs in breast cancer cells were studied. Light scattering based flow cytometry and microscopy were used for evaluating the uptake potential of MSPs by cells and the cellular autophagosome accumulation. Results showed bovine serum proteins significantly reduced the endocytosis of MSPs by decreasing their adsorption to cell membranes. Additionally, serum proteins had influences on the endocytic mechanisms of MSPs.Autophagosome accumulation could be caused by the internalized MSPs rather than the particles associated with cell membrane. Above fundamental findings promote our understandings upon the interactions of MSPs with cells. Light scattering based methods were proved to be simple and effective.The present work may promote their application in studies upon endocytosis of metallic particles in the future.
基金Supported by the National Natural Science Foundation of China under Grant No.11604227。
文摘High performance optical diode-like devices are highly desired in future practical nano-photonic devices with strong directional selectivity.We demonstrate a kind of giant broadband reciprocity optical diode-like devices by simultaneously using the directional Mie scattering effect and the asymmetric grating diffraction effect.The maximum asymmetric subtraction and the asymmetric transmission ratio can reach nearly 100%and 40dB at specified wavelength,respectively.In a wide waveband from 500nm to 800nm,the asymmetric subtraction and the ratio keep larger than 80%and 3.5 dB,respectively,even under oblique incidence.To the best of our knowledge,this is the best one-way-transmission effect observed in the reciprocity optical diode-like devices.In addition,we further demonstrate that this one-way-transmission effect can bring an effective absorption enhancement on gold films.The giant,broadband and angle-insensitive one-way-transmission effect demonstrated here is far beyond the well-known anti-reflection effect in the light-trapping devices and will bring new design philosophy for nano-photonic devices.
基金This work is supported by the National Key Research and Development Program of China(No.2017YFA0402300)National Natural Science Foundation of China(Nos.11874051,11564037,61741513,11904293)the Special Fund Project for Guiding Scientific and Technological Inno-vation of Gansu Province(No.2019zx-10).
文摘A state diagnosis of laser-produced plasma in air generated by a 1064 nm pulse laser was investigated by the Thomson scattering(TS)method.The evolutions of the electron temperature and electron density were obtained as a function of the time delay which ranged from 300-3200 ns.The heating effect produced by the 532 nm probe beam with different energies on the air plasma at different interaction times was further studied using a time-resolved optical emission spectroscopy technique.The influence of the probe beam on the electron density was found to be negligible,whereas its influence on electron temperature is evident.In addition,the heating effect of the probe beam on the plasma strongly depends on the energy of the probe beam,and gradually weakens with increasing time delay.Our results are helpful for further understanding the TS method and its application in plasma diagnostics.
文摘Calculation of the scattered field of the eccentric scatterers is an old problem with numerous applications. This study considers the interaction of a plane compressional sound wave with a liquid-encapsulated thermoviscous fluid cylinder submerged in an unbounded viscous thermally conducting medium. The translational addition theorem for cylindrical wave functions, the appropriate wave field expansions and the pertinent boundary conditions are employed to develop a closed-form solution in the form of infinite series. The analytical results are illustrated with a numerical example in which the compound cylinder is insonified by a plane sound wave at selected angles of incidence in a wide range of dimensionless frequencies. The backscattered far-field acoustic pressure amplitude and the spatial distribution of the total acoustic pressure in the vicinity of the cylinder are evaluated and discussed for representative values of the parameters characterizing the system. The effects of incident wave frequency, angle of incidence, fluid thermoviscosity, core eccentricity and size are thoroughly examined. Limiting case involving an ideal com- pressible liquid-coated cylinder is considered and fair agreement with a well-known solution is established.
文摘The K<SUP>+</SUP> scattering cross section with the in-medium virtual pion is evaluated in the lowest-order chiral perturbation theory with the density-dependent pion decay constant and mass. The contribution of nuclear pions to the total K<SUP>+</SUP>-nucleus cross section is found to be about 5% and 12% when the excess pion numbers per nucleon n<SUB>?</SUB> = 0.057 and 0.13 are used. The inclusion of the off-mass-shell behavior of the K<SUP>+</SUP>? amplitude produced a significant improvement in the K<SUP>+</SUP>-nucleus cross section.
基金National H-Tech Program under contract 863-7152101
文摘The rate of hydrothermal reaction of SiO_2 and/or A1_2O_3 in the system of CaO-Al_2O_3-SiO_2-H_2O at 200℃ and the factors which influence the reactions are investigated by determining the reaction ratio.The rate of reactions depends on the reactive activities of raw materials, initial composition of mixture and relative activity of SiO_2 and A12O3. The hydrothermal reaction can be accelerated by sodium hydroxide,in the case of silica,which has low activity, this is quite obvious.
文摘A new Monte Carlo simulation of the track structure of low-energy electrons （〈10keV） in liquid water is presented. The feature of the simulation is taken into consideration of the condensed-phase effect of liquid water on electron elastic scattering with the use of the Champion model, while the dielectric response formalism incorporating the optical-data model developed by Emfietzoglou et al. is applied for calculating the electron inelastic scattering. The spatial distributions of energy deposition and inelastic scattering events of low-energy electrons with different primary energies in liquid water are calculated and compared with other theoretical evaluations. The present work shows that the condensed-phase effect of liquid water on electron elastic scattering may be of the influence on the fraction of absorbed energy and distribution of inelastic scattering events at lower primary energies, which also indicate potential effects on the DNA damage induced by low-energy electrons.
基金supported by the National Key Research and Development Program of Chinathe National Natural Science Foundation of China (Grant Nos.2024YFA1408000,12474097,and2023YFA1406001)+2 种基金the Guangdong Provincial Quantum Science Strategic Initiative (Grant No.GDZX2201001)the Center for Computational Science and Engineering at Southern University of Science and Technology,the Major Science and Technology Infrastructure Project of Material Genome Big-science Facilities Platform supported by Municipal Development and Reform Commission of Shenzhen(for J.L.Z.and Y.L.)the Chinese funding sources applied via HPSTAR。
文摘The magnetic properties and Kondo effect in Ce_(3)TiBi_(5) with a quasi-one-dimensional structure were investigated using in situ high-pressure resistivity measurements up to 48 GPa.At ambient pressure,Ce_(3)TiBi_(5) undergoes an antiferromagnetic(AFM)transition at T_(N)∼5 K.Under high pressures within 8.9 GPa,we find that Kondo scattering contributes differently to the high-temperature resistance,R(T),depending on the applied current direction,demonstrating a significantly anisotropic Kondo effect.The complete P–T phase diagram has been constructed,in which the pressure dependence of T_(N) exhibits a dome-like shape.The AFM order remains robust under pressure,even when the coherence temperature T^(*) far exceeds 300 K.We attribute the observed anisotropic Kondo effect and the robust AFM to the underlying anisotropy in electronic hybridization under high pressure.
基金The project supportcd in part by the National Natural Science Foundation of China
文摘The results of comprehensive microscopic optical model calculations are pres-ented for the K<sup>+</sup> scattering from <sup>6</sup>Li,<sup>12</sup>C,<sup>28</sup>Si and <sup>40</sup>Ca at incident momenta 400-800MeV/c.The unconventional medium effect （i.e.the density-dependent correction forthe K<sup>+</sup>-nucleon scattering amplitude） is considered in two approaches.Both results arein agreement with recent experimental data.The influence of the correction on K<sup>+</sup> scat-tering from different nuclei are discussed in detail and only a weak dependence of thein-medium nucleon“swelling”effects on the mass number of target nuclei is found ex-cept for very light loosely-bound nucleus.
基金Projected supported by the National Natural Science Foundation of China(Grant No.11174182)the Specialized Research Fund for the Doctoral Program of Higher Education,China(Grant No.20110131110005)
文摘By making use of the quasi-two-dimensional （quasi-2D） model, the current-voltage （l-V） characteristics of In0AsA10.82N/A1N/GaN heterostructure field-effect transistors （HFETs） with different gate lengths are simulated based on the measured capacitance-voltage （C-V） characteristics and I-V characteristics. By analyzing the variation of the electron mobility for the two-dimensional electron gas （2DEG） with electric field, it is found that the different polarization charge distributions generated by the different channel electric field distributions can result in different polarization Coulomb field scatterings. The difference between the electron mobilities primarily caused by the polarization Coulomb field scatterings can reach up to 1522.9 cm2/V.s for the prepared In0.38AI0.82N/A1N/GaN HFETs. In addition, when the 2DEG sheet density is modulated by the drain-source bias, the electron mobility presents a peak with the variation of the 2DEG sheet density, the gate length is smaller, and the 2DEG sheet density corresponding to the peak point is higher.
