检索结果-南通市图书馆

Regulated polarization degree of upconversion luminescence and multiple anti-counterfeit applications

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 2172-2183页

作者： Dong-Ping Wen Ping Chen Yi Liang Xiao-Ming Mo Cao-Feng Pan Center On Nanoenergy Research Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and Technology Guangxi University Key laboratory of Micronano Energy and Sensor CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences

Polarization upconversion luminescence（PUCL） of lanthanide ions (Ln3+) has been widely used in single particle tracking,microfluidics detection,three-dimensional displays,and so on.However,no effective strategy has been developed for modulating PUCL.Here we report a strategy to regulate PUCL in Ho3+-doped NaYF4single nanorods based on the number of upconversion photons.By constructing a multiphoton upconversion system for Ho3+,we regulate the degree of polarization （DOP） of PUCL from 0.590 for two-photon luminescence to 0.929 for three-photon upconversion luminescence （UCL）.Furthermore,our strategy is verified from cross-relaxation between Ho3+and Yb3+,excitation wavelength,excitation power density,and local site symmetry.And this regulation strategy of PUCL has also been achieved in Tm3+,with the DOP ranging from 0.233 for two-photon luminescence to 0.925 for four-photon UCL Besides,multi-dimensional anti-counterfeiting display has been explored with PUCL.This work provides an effective strategy for regulating PUCL and also provides more opportunities for the development of polarization display optical encoding,anti-counterfeiting,and integrated optical devices.

关键词： Polarization upconversion luminescence Degree of polarization Population density of excited state Number of upconversion photons Polarization anti-counterfeiting display

View of thermodynamic phase transition of the charged Gauss-Bonnet AdS black hole via the shadow

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第4期33卷 355-362页

作者：何柯腱郭森罗智李国平 College of Physics Chongqing UniversityChongqing 401331China Guangxi Key laboratory for relativistic astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Physics and Astronomy China West Normal UniversityNanchong 637000China

We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow radius.In this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),and ensure thatαis positive to avoid any singularity problems.The equation derived for the shadow radius indicates that it increases as the event horizon radius increases,making it an independent variable for determining BH temperature.By investigating the PT curve in relation to shadows,we can observe that the shadow radius can be used as an alternative to the event horizon radius in explaining the phenomenon of BH PT.Furthermore,the results indicate that an increase in the parameterαcorresponds to a decrease in the temperature of the BH.By utilizing the relationship between the temperature and the shadow radius,it is possible to obtain the thermal profile of the Gauss-Bonnet AdS BH.It is evident that there is an N-type variation in temperature for pressures P

关键词： Gauss-Bonnet AdS black hole thermodynamic shadow

Optical trapping capability of tornado circular Pearcey beams

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第5期33卷 401-407页

作者：刘娜娜唐晓莹刘舜禹梁毅 Guangxi Key laboratory for relativistic astrophysics Center on Nanoenergy ResearchGuangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key laboratory of Featured Metal Materials and Lifecycle Safety for Composite Structures Nanning 530004China

We systemically investigate optical trapping capability of a kind of tornado waves on Rayleigh particles.Such tornado waves are named as tornado circular Pearcey beams(TCPBs)and produced by combining two circular Pearcey beams with different radii.Our theoretical exploration delves into various aspects,including the propagation dynamics,energy flux,orbital angular momentum,trapping force,and torque characteristics of TCPBs.The results reveal that the orbital angular momentum,trapping force,and torque of these beams can be finely tuned through the judicious manipulation of their topological charges(l_(1)and l_(2)).Notably,we observe a precise control mechanism wherein the force diminishes with|l_(1)+l_(2)|and|l_(1)-l_(2)|,while the torque exhibits enhancement by decreasing solely with|l_(1)+l_(2)|or increasing with|l_(1)-l_(2)|.These results not only provide quantitative insights into the optical trapping performance of TCPBs but also serve as a valuable reference for the ongoing development of innovative photonic tools.

关键词： trapping capability tornado beams autofocusing

Dark Matter Search in Dwarf Irregular Galaxies with Ten Years of Data from the Ice Cube Neutrino Observatory

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and astrophysics 2024年第3期24卷 75-82页

作者： Yi-Fei Lü Ben-Yang Zhu Rong-Lan Li Xue-Kang Guo Tian-Ci Liu Yong-Bo Huang Yun-Feng Liang Guangxi Key laboratory for relativistic astrophysicsSchool of Physical Science and TechnologyGuangxi University Nanning 530004China

Dwarf irregular galaxies(dIrrs),as rotationally supported systems,have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent years.In this paper,we use 10 yr of IceCube muon-track data and an unbinned maximum-likelihood-ratio method to search for neutrino signals beyond the background from the directions of seven dIrrs,aiming to detect neutrinos produced by heavy annihilation dark matter.We do not detect any significant signal.Based on such null results,we calculate the upper limits on the velocity-averaged annihilation cross section for 1 TeV–10 PeV dark matter.Our limits,although weaker than the strictest constraints in the literature in this mass range,are also a good complement to the existing results considering the more reliable J-factor measurements of dIrrs.

关键词： (cosmology) dark matter-cosmology theory-galaxies dwarf

Design and prototyping of the readout electronics for the transition radiation detector in the high energy cosmic radiation detection facility

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第4期35卷 189-199页

作者： Jie-Yu Zhu Yang-Zhou Su Hai-Bo Yang Fen-Hua Lu Yan Yang Xi-Wen Liu Ping Wei Shu-Cai Wan Hao-Qing Xie Xian-Qin Li Cong Dai Hui-Jun Hu Hong-Bang Liu Shu-Wen Tang Cheng-Xin Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Guangxi Key laboratory for relativistic astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

The high energy cosmic-radiation detection(HERD)facility is planned to launch in 2027 and scheduled to be installed on the China Space Station.It serves as a dark matter particle detector,a cosmic ray instrument,and an observatory for high-energy gamma rays.A transition radiation detector placed on one of its lateral sides serves dual purpose,(ⅰ)calibrating HERD's electromagnetic calorimeter in the TeV energy range,and(ⅱ)serving as an independent detector for high-energy gamma rays.In this paper,the prototype readout electronics design of the transition radiation detector is demonstrated,which aims to accurately measure the charge of the anodes using the SAMPA application specific integrated circuit chip.The electronic performance of the prototype system is evaluated in terms of noise,linearity,and resolution.Through the presented design,each electronic channel can achieve a dynamic range of 0–100 fC,the RMS noise level not exceeding 0.15 fC,and the integral nonlinearity was<0.2%.To further verify the readout electronic performance,a joint test with the detector was carried out,and the results show that the prototype system can satisfy the requirements of the detector's scientific goals.

关键词： HERD Dark matter particle detection TRD Readout electronics SAMPA Data acquisition Performance test

Observational appearance and extra photon rings of an asymmetric thin-shell wormhole with a Bardeen profile

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第6期48卷 211-221页

作者：何柯腱罗智郭森李国平 Department of Physics Chongqing UniversityChongqing 401331China Guangxi Key laboratory for relativistic astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Physics and Astronomy China West Normal UniversityNanchong 637000China

In this work,the optical appearance of an asymmetric thin-shell wormhole with a Bardeen profile is studied.To initiate the process,we need to construct an asymmetric thin-shell wormhole utilizing the cut-and-paste technique proposed by Visser and subsequently ascertain its pertinent physical quantities such as the radius of the photon sphere and critical impact parameters for different values of magnetic charge g.Then,the effective potential and motion behavior of photons are also investigated within the framework of asymmetric thin-shell wormholes with a Bardeen profile.It can be found that the effective potential,ray trajectory,and azimuthal angle of the thin-shell wormhole exhibit a strong correlation with the mass ratio of black holes.By considering the accretion disk as the sole background light source,we observe additional photon rings and lensing bands in the optical appearance of the asymmetric thin-shell wormhole with a Bardeen profile compared to those exhibited by the Bardeen black hole.One can find that there is an increase in the size of the specific additional light bands with increasing magnetic charge g,which is different from the black hole case.These exceptionally luminous rings can serve as a robust criterion for the identification and characterization of the thin-shell wormhole spacetime.

关键词： shadow asymmetric thin-shell wormhole Bardeen black hole

Rastall gravity:accretion disk image in the context of radiation fields and visual transformations compared to Reissner-Nordström black hole

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第4期48卷 174-182页

作者：黄宇翔郭森梁宇崔宇昊蒋青权林恺 School of Physics and Astronomy China West Normal UniversityNanchong 637000China Guangxi Key laboratory for relativistic astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Hubei Subsurface Multi-scale Imaging Key laboratory Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China

In this study,we investigated the astronomical implications of Rastall gravity,particularly its behavior amidst a radiation field compared to Reissner-Nordström(RN)black holes.We found a crucial correlation between the dynamics of the accretion disk and the parameters Q and Nr,which properly reflect the influence of spacetime metrics on the disk’s appearance.Elevated electric charge Q causes contraction in the disk’s orbit due to enhanced gravitational effects,while higher Nr values lead to outward expansion,influenced by the attributes of the radiation field.Interestingly,the charged black holes surrounded by radiation fields exhibit distinct visual disparities from RN black holes.Brightness decreases and expansion occurs within the innermost stable circular orbit of the accretion disk with rising Nr values.Our study also reveals the process by which the accretion disk transitions from a conventional disk-like structure to a hat-like form at different observation angles,with the redshift effect gradually intensifying.Moreover,the results of the considered Rastall gravity radiation field are consistent with the constraints of the gravitational lensing of the host galaxy on Rastall gravity parameters,thereby enhancing the consistency between theoretical predictions and actual observations.

关键词： Rastall theory optical appearance thin accretion disk

Robust autofocusing propagation in turbulence

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第6期33卷 370-375页

作者：刘娜娜谭柳陈凯健洪佩龙莫小明邹炳锁任煜轩梁毅 Guangxi Key laboratory for relativistic astrophysics Center on Nanoenergy ResearchSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Mathematics and Physics Anqing Normal UniversityAnqing 246133China Institute for Translational Brain Research MOE Frontiers Center for Brain ScienceFudan UniversityShanghai 200032China

Turbulence in complex environments such as the atmosphere and biological media has always been a great challenge to the application of beam propagation in optical communication, optical trapping and manipulation. To overcome this challenge, this study comprehensively investigates the robust propagation of traditional Gaussian and autofocusing beams in turbulent environments. In order to select stable beams that exhibit high intensity and high field gradient at the focal position in complex environments, Kolmogorov turbulence theory is used to simulate the propagation of beams in atmospheric turbulence based on the multi-phase screen method. We systematically analyze the intensity fluctuations, the variation of the coherence factor and the change in the scintillation index with propagation distance. The analysis reveals that the intensity fluctuations of autofocusing beams are significantly smaller than those of Gaussian beams, and the coherence of autofocusing beams is better than that of Gaussian beams under turbulence. Moreover, autofocusing beams exhibit less oscillation than Gaussian beams, indicating that autofocusing beams propagate in complex environments with less distortion and intensity fluctuation. Overall, this work clearly demonstrates that autofocusing beams exhibit higher stability in propagation compared with Gaussian beams, showing great promise for applications such as optical trapping and manipulation in complex environments.

关键词： propagation beams autofocusing turbulence

GRB 200612A:An Ultralong Gamma-Ray Burst Powered by Magnetar Spinning Down

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and astrophysics 2024年第2期24卷 190-195页

作者：陈良军王祥高杨德龙梁恩维 Guangxi Key laboratory for relativistic astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

GRB 200612A could be classified as an ultralong gamma-ray burst due to its prompt emission lasting up to~1020 s and the true timescale of the central engine activity t_(burst)≥4×10^(4) s.The late X-ray light curve with a decay index ofα=7.53 is steeper than the steepest possible decay from an external shock model.We propose that this X-ray afterglow can be driven by dipolar radiation from the magnetar spindown during its early stage,while the magnetar collapsed into the black hole before its spindown,resulting in a very steep decay of the late X-ray light curve.The optical data show that the light curve is still rising after 1.1 ks,suggesting a late onset.We show that GRB 200612A’s optical afterglow light curve is fitted with the forward shock model by Gaussian structured off-axis jet.This is a special case among GRBs,as it may be an ultralong gamma-ray burst powered by a magnetar in an off-axis observation scenario.

关键词： (stars:)gamma-ray burst individual(GRB 200612A)-(stars:)gamma-ray burst general-stars magnetars