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Analytical Solutions to the D-Dimensional Schrodinger Equation with the Eckart Potential

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Chinese physics Letters 2016年第1期33卷 10-13页

作者：高洁张民仓 College of Physics and Information Technology Shaanxi Normal University

The analytical solutions to the Schrodinger equation with the Eckart potential in arbitrary dimension D is investigated by using the Nikiforov-Uvarov method, and the centrifugal term is treated approximatively with the scheme of Greene and Aldrich. The discrete spectrum is obtained and the wavefunetion is expressed in terms of the Jacobi polynomial or the hypergeometric function. Some special cases of the Eckart potential are discussed for D=3, and the resulting energy equation agrees well with that obtained by other methods.

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Enhancement of red emission by co-dopant Ln^(3+) ions in Eu^(3+) :LaOF nanoparticles

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Science China(physics,Mechanics & Astronomy) 2013年第5期56卷 928-932页

作者： FU ZhenXing ZHENG HaiRong HE EnJie GAO Wei LI GuiAn College of Physics and Information Technology Shaanxi Normal University College of Physics and Information Technology Ningxia Normal University

Fluoride nanoparticles of Ln3+(Ln3+=Pr3+,Nd3+,Sm3+,Gd3+,Tb3+Dy3+,Ho3+,Er3+,Tm3+,Yb3+)/Eu3+:LaOF and Eu3+ :LaOF with rhombohedral crystal structure were prepared by a hydrothermal-sintering method. The red fluorescence emission of Eu3+ ions was found to be enhanced with most of the co-dopant Ln3+ ions. Compared with strong fluorescence emission at 610 nm of Eu3+ :LaOF nanoparticles, the enhancement factors was up to ten times in Ln3+(Ln3+ =Gd3+,Dy3+,Tm3+)/Eu3+ :LaOF co-doped nanoparticles. The results show that the asymmetry of the local environment of Eu3+ ion was reduced by co-doping Ln3+ ion into the nanoparticles, and that energy transfer might occur between Eu3+ and codopant Ln3+ ions, which is suggested as the source of the observed fluorescence enhancement.

关键词：稀土离子纳米粒子共掺杂铕离子红光发射粒子增强荧光增强作用荧光发射

First-principle study of the structural,electronic,and optical properties of SiC nanowires

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Chinese physics B 2017年第5期26卷 333-338页

作者：张威虎张富春张伟斌张绍林 Woochul Yang Communication and information Engineering college Xi'an University of Science and Technology college of physics and Electronic information Yan'an University Department of physics Dongguk University

We preform first-principle calculations for the geometric, electronic structures and optical properties of SiC nanowires（NWs）. The dielectric functions dominated by electronic interband transitions are investigated in terms of the calculated optical response functions. The calculated results reveal that the SiC NW is an indirect band-gap semiconductor material except at a minimum SiC NW（n = 12） diameter, showing that the NW（n = 12） is metallic. Charge density indicates that the Si–C bond of SiC NW has mixed ionic and covalent characteristics： the covalent character is stronger than the ionic character, and shows strong s–p hybrid orbit characteristics. Moreover, the band gap increases as the SiC NW diameter increases. This shows a significant quantum size and surface effect. The optical properties indicate that the obvious dielectric absorption peaks shift towards the high energy, and that there is a blue shift phenomenon in the ultraviolet region. These results show that SiC NW is a promising optoelectronic material for the potential applications in ultraviolet photoelectron devices.

关键词： ultraviolet dielectric photoelectron metallic ionic covalent transitions optoelectronic valence imaginary

Effective method to control the levitation force and levitation height in a superconducting maglev system

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Chinese physics B 2015年第11期24卷 483-487页

作者：杨芃焘杨万民王妙李佳伟郭玉霞 College of Physics and Information Technology Shaanxi Normal University

The influence of the width of the middle magnet in the permanent magnet guideways （PMGs） on the levitation force and the levitation height of single-domain yttrium barium copper oxide （YBCO） bulks has been investigated at 77 K under the zero field cooled （ZFC） state. It is found that the largest levitation force can be obtained in the system with the width of the middle magnet of the PMG equal to the size of the YBCO bulk when the gap between the YBCO bulk and PMG is small. Both larger levitation force and higher levitation height can be obtained in the system with the width of the middle magnet of the PMG larger than the size of the YBCO bulk. The stiffness of the levitation force between the PMG and the YBCO bulk is higher in the system with a smaller width of the middle magnet in the PMG. These results provide an effective way to control the levitation force and the levitation height for the superconducting maglev design and applications.

关键词： permanent magnet guideway levitation force levitation height

The dawn−dusk asymmetry in mesosphere and lower thermosphere temperature disturbances during geomagnetic storms at high latitude

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Earth and Planetary physics 2024年第2期8卷 356-367页

作者： GuanChun Wei JianYong Lu Fen Tang JingYuan Li Meng Sun Institute of Space Weather School of Atmospheric PhysicsNanjing University of Information Science&TechnologyNanjing 210044China college of information and Communication National University of Defense TechnologyWuhan 430019China

Utilizing observations by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument,we quantitatively assessed the dawn-dusk asymmetry in temperature disturbances within the high-latitude mesosphere and lower thermosphere(MLT)during the main phase of geomagnetic storms in this study.An analysis of five geomagnetic superstorm events indicated that during the main phase,negative temperature disturbances were more prevalent on the dawn side than on the dusk side in the high-latitude MLT region.Results of a statistical analysis of 54 geomagnetic storm events also revealed a notable disparity in temperature disturbances between the dawn and dusk sides.At high latitudes,38.2%of the observational points on the dawn side exhibited negative temperature disturbances(less than−5 K),whereas on the dusk side,this percentage was only 29.5%.In contrast,at mid-latitudes,these proportions were 34.1%and 36.5%,respectively,showing no significant difference.We also conducted a statistical analysis of temperature disturbances at different altitudes,which revealed an increase in the proportion of warming disturbances with altitude.Conversely,the proportion of cooling disturbances initially rose with altitude,reaching a peak around 105 km,and subsequently decreased.These temperature disturbance differences could be explained by the day-night asymmetry in vertical wind disturbances during storm conditions.

关键词： dawn dusk asymmetry SABER(Sounding of the Atmosphere using Broadband Emission Radiometry) geomagnetic storms mesosphere and lower thermosphere

基于金属织物和自然摩擦带电的电子皮肤对人体运动的智能识别

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Science China Materials 2024年第3期67卷 887-897页

作者：徐锦杰陈婉翟刘樑杰江姗姗王浩楠张家翔甘昕艳周雄图郭太良吴朝兴张永爱 college of physics and information Engineering Fuzhou UniversityFuzhou 350108China Fujian Science&technology Innovation Laboratory for Optoelectronic information of China Fuzhou 350108China

目前已开发出各种基于电子或光学信号的技术来感知身体运动,这在医疗保健、康复和人机交互等领域至关重要.然而,这些信号都是从身体外部获取的.本研究中,我们制备了一种电子皮肤(e-skin)人体运动传感器,它利用有机聚合物和金属织物的组... 详细信息

目前已开发出各种基于电子或光学信号的技术来感知身体运动,这在医疗保健、康复和人机交互等领域至关重要.然而,这些信号都是从身体外部获取的.本研究中,我们制备了一种电子皮肤(e-skin)人体运动传感器,它利用有机聚合物和金属织物的组合,通过人体的自然电荷感应(EI)来检测运动.该电子皮肤可获得高达450 V的人体电势信号.此外,该信号可通过最先进的深度学习技术自动提取和训练.该传感器能准确识别睡眠活动,准确率约为96.55%.这种可穿戴运动传感器可以与物联网技术无缝集成,实现多功能应用,展示了其在人类活动识别和人工智能方面的潜在用途.

关键词： human activity recognition e-skin sleep motion recognition contact-separation electrification 1D-CNN

The electronic,optical,and thermodynamical properties of tetragonal,monoclinic,and orthorhombic M_3N_4(M=Si,Ge,Sn):A first-principles study

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Chinese physics B 2017年第4期26卷 313-320页

作者：陈东程科齐蓓影 college of physics and Electronic Engineering Xinyang Normal University college of Optoelectronic technology Chengdu University of Information Technology

A detailed study of the M_3N_4（M = Si,Ge,Sn） nitrides in their tetragonal,monoclinic and orthorhombic phases has been performed with the plane-wave pseudo-potential method combined with the quasi-harmonic approximation,including the phononic effects.We rationalize the main puzzle,i.e.,the fundamental properties of these phases are unclear,by calculating the crystal structures,density of states,and optical properties.The direct band gaps of t-Ge_3N_4,m-Si_3N_4,and o-Ge_3N_4 benefit the opto-electrical properties,t-,m-,and o-Si_3N_4 can be used as refractive materials while m-M_3N_4（M = Si,Ge,Sn） are optically transparent in the visible light region.Our results improve the understanding of the detailed electronic structures of all compounds,as well as the influences of electronic structure on their stabilities.Furthermore,we find that thermodynamic quantities are sensitive to structures and,therefore,depend on various temperature and pressure conditions.

关键词： first-principles density of states optical properties nitrides

Probing the structure of multi-center molecules with odd–even high harmonics

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Chinese physics B 2018年第5期27卷 274-280页

作者：苏宁于术娟李卫艳杨世平陈彦军 College of Physics and Information Technology Shaan’xi Normal University college of physics and information Engineering Hebei Normal University School of Mathematics and Science Hebei GEO University

We study high-order harmonic generation（HHG） from multi-center asymmetric linear molecules numerically and analytically. Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respond differently to the change of the molecular structure. Specifically, when the internuclear distances between these nuclei of the molecule have a small change, the odd spectra usually do not change basically, but the even spectra differ remarkably. Based on this phenomenon, a simple procedure is proposed to probe the positions of these nuclei with odd–even HHG. Our results shed light on attosecond probing of the structure of multi-center molecules using HHG.

关键词： odd-even harmonics multi-center asymmetric molecules molecular structure

Application of high-pressure technology in exploring mechanical properties of high-entropy alloys

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Tungsten 2023年第1期5卷 50-66页

作者： Shu-Cong Li Qing-Lin Wang Yu Yao Dan-Dan Sang Hai-Wa Zhang Guo-Zhao Zhang Cong Wang Cai-Long Liu Shandong Key Laboratory of Optical Communication Science and technology School of Physics Science&Information TechnologyLiaocheng UniversityLiaocheng 252059China college of Mathematics and physics Beijing University of Chemical TechnologyBeijing 100029China

In recent years,high-entropy alloys(HEAs) have developed a lot as the new style of materials,which have become a research focus in the materials fields.It breaks the normal procedure of traditional alloy design(based on one/two elements as the main component,and adds some other elements to improve the micro structure and required related performance of the alloy),and consists of five or more equal or nearly equal elements,with multiple principal elements.Therefore,HEAs have many excellent mechanical properties compared with traditional alloys,which have aroused great research interest of researchers.The rapid development of high-pressure technology makes it a powerful tool to modulate the structures of HEAs,and brings new chance for the study and optimization of mechanical properties of HEAs.In this paper,the application of high-pressure technology in exploring and improving the mechanical properties of HEAs is reviewed,which could deepen the understanding of high-pressure technology and provide a new avenue for further exploration of HEAs’ mechanical properties.

关键词： High-entropy alloys Mechanical properties High-pressure torsion High-pressure Diamond anvil cells