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Measurement of quantum defects of nS and nD states using field ionization spectroscopy in ultracold cesium atoms 被引量:1
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作者 张临杰 冯志刚 +3 位作者 李安玲 赵建明 李昌勇 贾锁堂 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第5期1838-1842,共5页
This paper reports that ultracold atoms are populated into different nS and nD Rydberg states (n=25-52) by two-photon excitation. The ionization spectrum of an ultracold Rydberg atom is acquired in a cesium magneto-... This paper reports that ultracold atoms are populated into different nS and nD Rydberg states (n=25-52) by two-photon excitation. The ionization spectrum of an ultracold Rydberg atom is acquired in a cesium magneto-optical trap by using the method of pulse field ionization. This denotes nS and nD states in the ionization spectrum and fits the data of energy levels of different Rydberg states to obtain quantum defects of nS and nD states. 展开更多
关键词 ultracold Rydberg atoms quantum defect field ionization spectrum two-photon excitation
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An effective quantum defect theory for the diamagnetic spectrum of a barium Rydberg atom
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作者 李波 刘红平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期23-26,共4页
A theoretical calculation is carried out to investigate the spectrum of a barium Rydberg atom in an external magnetic field. Using an effective approach incorporating quantum defect into the centrifugal term in the Ha... A theoretical calculation is carried out to investigate the spectrum of a barium Rydberg atom in an external magnetic field. Using an effective approach incorporating quantum defect into the centrifugal term in the Hamiltonian, we reexamine the reported spectrum of the barium Rydberg atom in a magnetic field of 2.89 T [J. Phys. B 28 L537 (1995)]. Our calculation employs B-spline basis expansion and complex coordinate rotation techniques. For single photon absorption from the ground 6s2 to 6snp Rydberg states, the spectrum is not influenced by quantum defects of channels ns and nd. The calculation is in agreement with the experimental observations until the energy reaches E = -60 cm-1. Beyond this energy, closer to the threshold, the calculated and experimental results do not agree with each other. Possible reasons for their discrepancies are discussed. Our study affirms an energy range where the diamagnetic spectrum of the barium atom can be explained thoroughly using a hydrogen model potential. 展开更多
关键词 diamagnetic spectrum quantum defect barium Rydberg atom
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Energy level analyses of even-parity J=1 and 2 Rydberg states of Sn I by multichannel quantum defect theory
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作者 由帅 凤艳艳 戴振文 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第6期2229-2237,共9页
This paper analyzes the energy levels along the even-parity J = 1 and 2 Rydberg series of Sn I by multichannel quantum defect theory. A good agreement between theoretical and experimental energy levels was achieved. B... This paper analyzes the energy levels along the even-parity J = 1 and 2 Rydberg series of Sn I by multichannel quantum defect theory. A good agreement between theoretical and experimental energy levels was achieved. Below 59198 cm^-1, a total of 85 and 23 new energy levels, respectively, in the J = 1 and J = 2 series, which cannot be measured previously by experiments, are predicted in this work. Based on the calculated admixture coefficients of each channel, interchannel interactions were discussed in detail. The results are helpful to understand the characteristics of configuration interaction among even-parity levels in Sn I. 展开更多
关键词 atom Sn Rydberg state multichannel quantum defect theory
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Exact quantum defect theory approach for lithium in magnetic fields
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作者 徐家坤 陈海清 刘红平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期183-186,共4页
We calculate the diamagnetic spectrum of lithium at highly excited states up to the positive energy range using the exact quantum defect theory approach. The concerned excitation is one-photon transition from the grou... We calculate the diamagnetic spectrum of lithium at highly excited states up to the positive energy range using the exact quantum defect theory approach. The concerned excitation is one-photon transition from the ground state 2s to the highly excited states np with π and σ polarizations respectively. Lithium has a small quantum defect value 0.05 for the np states, and its diamagnetic spectrum is very similar to that of hydrogen in the energy range approaching the ionization limit. However, a careful calculation shows that the spectrum has a significant discrepancy with that of hydrogen when the energy is lower than -70 cm-1. The effect of the quantum defect is also discussed for the Stark spectrum. It is found that the σ transition to the np states in an electric field has a similar behavior to that of hydrogen due to zero interaction with channel ns. 展开更多
关键词 diamagnetic spectrum quantum defect theory
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Energy levels of perturbed 6pnd J = 2 Rydberg states of Pb I by multichannel quantum defect theory
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作者 戴振文 蒋红玫 +2 位作者 刘靖尧 彭慰先 蒋占魁 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2003年第5期542-551,共10页
Energy levels of the odd-parity 6pnd J=2 Rydberg states of atomic lead are analyzed by the multichannel quantum defect theory (MQDT) with previous experimental energy levels. The obtained. Using these parameters, admi... Energy levels of the odd-parity 6pnd J=2 Rydberg states of atomic lead are analyzed by the multichannel quantum defect theory (MQDT) with previous experimental energy levels. The obtained. Using these parameters, admixture coefficients for each level are calculated to designate the level denotations. The results show that strong channel mixings exist for the levels near the 6pnd (3/2)[5/2]2 0 and 6p6d (3/2)[3/2]2 0 pertubers. The five-channel model different from that in literature is used to predict 21 energy positions of 6pnd (1/2)[3/2]2 0 levels and to determine the denotations of all the 6pnd J=2 Rydberg states under 59788 cm?1 for Pb I. 展开更多
关键词 lead RYDBERG energy level MULTICHANNEL quantum defect theory.
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高磁场下7Li原子的d波Feshbach共振
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作者 陈钟之 赖海健 +1 位作者 齐燃 俞振华 《物理学报》 北大核心 2025年第9期250-256,共7页
Feshbach共振是在特定外场下原子间发生共振相互作用的现象,主要表现为在共振附近量化低能散射性质的广义散射长度随外场趋于发散.近年来,随着冷原子物理的发展,s波及高分波的Feshbach共振相继被发现,为研究共振相互作用在多体物理中的... Feshbach共振是在特定外场下原子间发生共振相互作用的现象,主要表现为在共振附近量化低能散射性质的广义散射长度随外场趋于发散.近年来,随着冷原子物理的发展,s波及高分波的Feshbach共振相继被发现,为研究共振相互作用在多体物理中的效应提供了宝贵的途径.本文基于多通道量子缺陷理论(MQDT),预言在1039.24和1055.64 G(1 G=10^(-4)T)外磁场下,7Li原子间存在两个d波Feshbach共振,并确定了共振的各项参数,如共振宽度等.同时,估计了磁偶极矩相互作用对这两个共振的影响.本文的结果拓展了在7Li原子气体中研究d波共振相互作用的契机. 展开更多
关键词 FESHBACH 共振 多通道量子缺陷理论
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二维SiSnF_(2)中非磁性缺陷的影响和量子尺寸效应
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作者 刘文超 罗朝波 +1 位作者 谢紫彤 彭向阳 《物理学报》 北大核心 2025年第6期191-200,共10页
一般认为拓扑绝缘体对非磁性缺陷是高度免疫的,但是在器件应用的介观尺度上还缺乏验证.本文以SiSnF_(2)单层条带为例,研究了不同缺陷浓度和尺寸对拓扑绝缘体电子输运的影响.第一性原理计算发现,SiSnF_(2)在大于2%的拉伸应变下转变为拓... 一般认为拓扑绝缘体对非磁性缺陷是高度免疫的,但是在器件应用的介观尺度上还缺乏验证.本文以SiSnF_(2)单层条带为例,研究了不同缺陷浓度和尺寸对拓扑绝缘体电子输运的影响.第一性原理计算发现,SiSnF_(2)在大于2%的拉伸应变下转变为拓扑绝缘体.用遗传算法拟合了有效紧束缚模型的参数,计算了拓扑绝缘体SiSnF_(2)条带输运性质,发现边缘态也可能被随机空位缺陷破坏.对于长18.8 nm、宽8.2 nm的条带,在没有缺陷时,电流集中在条带边缘,电导为拓扑边缘态的理想值2e^(2)/h.当缺陷浓度为1%时,边缘电流已被明显扰动,但背散射仍受到有效抑制,电流绕过缺陷向前传输.当浓度为5%时,边缘电子经散射深入条带内部,与另一边缘发生散射,破坏了拓扑边缘态,使电导降为0.6e^(2)/h.因此,缺陷导致的由拓扑绝缘体到普通绝缘体的转变是渐变而不是突变.研究发现了明显的输运量子尺寸效应,增大条带宽度可减小边缘间电子散射,增强拓扑边缘态的稳定性;而增大长度会增大电子的局域性和边缘间电子散射,降低拓扑边缘态的稳定性. 展开更多
关键词 拓扑绝缘体 电子输运 缺陷 量子尺寸效应
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USTERQUANTUM3型清纱器清纱疵点分析与跟踪 被引量:1
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作者 王俊英 《棉纺织技术》 CAS 北大核心 2023年第9期60-63,共4页
为充分发挥USTER QUANTUM 3型清纱器的清纱效能,减少布面纱线疵点,对该清纱器的清纱疵点NSLT的分析方法和来源追溯进行研究。分析了NSLT纱疵的外形特点和产生原因。研究结果表明:利用清纱器的抓纱疵功能,将纱疵收集在纱疵卡上分析纱疵来... 为充分发挥USTER QUANTUM 3型清纱器的清纱效能,减少布面纱线疵点,对该清纱器的清纱疵点NSLT的分析方法和来源追溯进行研究。分析了NSLT纱疵的外形特点和产生原因。研究结果表明:利用清纱器的抓纱疵功能,将纱疵收集在纱疵卡上分析纱疵来源,结合用户反馈可进一步优化清纱工艺参数;通过清纱器的“概况”功能,可以观察某个班次某种纱疵概况和每个锭子的具体情况,对波动大的纱疵应分析原因,对纱疵出现频率高的锭子应追溯纱疵来源。认为:企业应建立纱疵监控数据、模拟图跟踪机制,制定跟踪计划,一旦发现纱疵数据和纱疵模拟图变化较大,可立即启动突发性纱疵分析机制,以减少布面质量波动、原材料消耗和机物料消耗。 展开更多
关键词 USTER quantum 3型清纱器 清纱疵点 抓纱疵 纱疵卡 模拟图
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长波段半导体激光泵浦光纤激光器实现2 kW功率输出 被引量:1
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作者 王鹏 孟祥明 +11 位作者 吴函烁 叶云 杨保来 奚小明 史尘 张汉伟 王小林 习锋杰 王泽锋 许晓军 周朴 陈金宝 《强激光与粒子束》 CAS CSCD 北大核心 2024年第3期82-84,共3页
半导体激光(LD)泵浦的高功率光纤激光器具有效率高、体积小、重量轻、稳定性好等优点,在工业加工等诸多领域都有着广泛的应用。为了提高泵浦光吸收率,传统光纤激光器常用915 nm和976 nm波段的LD作为激光的泵浦源。在该类LD泵浦的光纤激... 半导体激光(LD)泵浦的高功率光纤激光器具有效率高、体积小、重量轻、稳定性好等优点,在工业加工等诸多领域都有着广泛的应用。为了提高泵浦光吸收率,传统光纤激光器常用915 nm和976 nm波段的LD作为激光的泵浦源。在该类LD泵浦的光纤激光器中,由于量子亏损和泵浦吸收系数相对较高,光纤激光器的热致模式不稳定(TMI)阈值相对较低。为了提高量子效率和潜在的TMI阈值,提出采用大于1010 nm波段的LD直接泵浦光纤激光器,产生高量子效率激光。搭建了振荡放大一体化的全光纤激光器,采用总泵浦功率为2.56 kW的1010 nm波段LD泵浦,首次获得输出功率2.05 kW、光束质量M^(2)约1.7的激光。后续将通过进一步增大泵浦功率、优化光纤特性以实现更高功率、更优光束质量的光纤激光输出。 展开更多
关键词 光纤激光器 量子亏损 振荡放大一体化 模式不稳定
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Influence of Modified ZnO Quantum Dots and Nanostructures as New Antibacterials 被引量:1
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作者 Zahra Fakhroueian Faraz M. Harsini +3 位作者 Firoozeh Chalabian Fatemeh Katouzian Azizollah Shafiekhani Pegah Esmaeilzadeh 《Advances in Nanoparticles》 2013年第3期247-258,共12页
Antibacterial activities of various spherical zinc oxide nanoparticles and nano special morphological structures including quantum dots, nanorod arrays, nanoporous shapes and needle-like crystals had been investigated... Antibacterial activities of various spherical zinc oxide nanoparticles and nano special morphological structures including quantum dots, nanorod arrays, nanoporous shapes and needle-like crystals had been investigated as new nanomedicine compounds. Also antibacterial activity based on minimal inhibitory concentration and the growth inhibitory zone (well method) was evaluated. ZnO nanostructures were fabricated by novel hydrolysis sol-gel-hydrothermal process followed with rapid quenching as new technique using glycerine, vegetable fatty esters such as coconut, sunflower and Lauric alcohol ethoxylated as organic templates soluble in eco-friendly nanofluids. The results showed that Bacillus anthracis and Pseudomonas aerogenes were extremely sensitive to treatment with unique ZnO nanostructured. Their growth inhibitory zone presented 30 mm and 25 mm inhibition zone with better inhibitory effect compared to the Gentamicin antibiotic standard. ZnO nanostructures had also been indicated to have a wide range of antibacterial activities against both Gram-positive and Gram-negative bacteria especially more effective on (gr+) species using the growth inhibitory zone. We could design and make significant formulations of fatty acids and esters-capped ZnO quantum dots nanofluids which created high promising agents for controlling Anthrax, Staphylococcus epidermidis and their influences in antimicrobial properties with low cost for future. 展开更多
关键词 NANOBIOTECHNOLOGY ANTIBACTERIAL Activity HYDROLYSIS Sol-Gel-Hydrothermal ZnO quantum DOTS MIC and Well Method Complex defects
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位移电流测试方法的改进及应用 被引量:1
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作者 纪文宇 张汉壮 《物理与工程》 2024年第1期30-34,66,共6页
自从麦克斯韦第一次提出位移电流这一概念之后,其在薄膜表征中便得到广泛的应用。然而,在课堂教学中,极少涉及位移电流的测试原理及相关应用讲解,更缺少对其实际应用的介绍。本文从位移电流的测试原理出发,联系实际应用,提出了基于周期... 自从麦克斯韦第一次提出位移电流这一概念之后,其在薄膜表征中便得到广泛的应用。然而,在课堂教学中,极少涉及位移电流的测试原理及相关应用讲解,更缺少对其实际应用的介绍。本文从位移电流的测试原理出发,联系实际应用,提出了基于周期性阶跃电压驱动的电流测量(CPSIV)的新方法。这将有效地加深学生对于位移电流物理本质的深入理解。同时,我们以量子点发光二极管(QLED)为平台,对这一新的测试方案进行了实验验证。针对其中空穴传输层薄膜的缺陷特性及其对器件性能的影响进行了表征,揭示了器件的发光开启机制,证实了我们方案的可靠性。 展开更多
关键词 麦克斯韦方程 位移电流 周期性阶跃电压 长寿命缺陷态 量子点发光二极管
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Automatic Image Inspection of Fabric Defects Based on Optimal Gabor Filter
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作者 尉苗苗 李岳阳 +1 位作者 蒋高明 丛洪莲 《Journal of Donghua University(English Edition)》 EI CAS 2016年第4期545-548,共4页
An effective method for automatic image inspection of fabric defects is presented. The proposed method relies on a tuned 2D-Gabor filter and quantum-behaved particle swarm optimization( QPSO) algorithm. The proposed m... An effective method for automatic image inspection of fabric defects is presented. The proposed method relies on a tuned 2D-Gabor filter and quantum-behaved particle swarm optimization( QPSO) algorithm. The proposed method consists of two main steps:( 1) training and( 2) image inspection. In the image training process,the parameters of the 2D-Gabor filters can be tuned by QPSO algorithm to match with the texture features of a defect-free template. In the inspection process, each sample image under inspection is convoluted with the selected optimized Gabor filter.Then a simple thresholding scheme is applied to generating a binary segmented result. The performance of the proposed scheme is evaluated by using a standard fabric defects database from Cotton Incorporated. Good experimental results demonstrate the efficiency of proposed method. To further evaluate the performance of the proposed method,a real time test is performed based on an on-line defect detection system. The real time test results further demonstrate the effectiveness, stability and robustness of the proposed method,which is suitable for industrial production. 展开更多
关键词 fabric defect detection optimal Gabor filter quantum-behaved particle swarm optimization(QPSO) algorithm image segmentation
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铯原子nD里德堡态量子亏损的精密测量
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作者 范伟娜 宜旭阳 +2 位作者 康智强 张好 杨文广 《量子光学学报》 北大核心 2024年第3期53-61,共9页
量子亏损是碱金属原子低轨道角动量的特有性质,它主要源于最外层电子轨道与离子实相互作用所引起的能量变化,导致碱金属低轨道角动量态的能量与氢原子相应能级相比产生较大的频移。在里德堡原子波函数的数值计算过程中,量子亏损会影响... 量子亏损是碱金属原子低轨道角动量的特有性质,它主要源于最外层电子轨道与离子实相互作用所引起的能量变化,导致碱金属低轨道角动量态的能量与氢原子相应能级相比产生较大的频移。在里德堡原子波函数的数值计算过程中,量子亏损会影响里德堡能级的精确值,从而影响波函数的计算精确度,对于里德堡原子的极化率计算、基于里德堡原子的微波电场测量等理论研究和实验测量精确度的提高有重要的意义。原子的电磁诱导透明效应(Electromagnetically-Induced-Transparency,EIT)提供了一种实现精密测量里德堡能级的技术手段。通过双光子激发方法将室温蒸汽池中的原子激发到里德堡态,利用电磁诱导透明光谱测量了nD_(5/2)和nD_(3/2)态(50≤n≤70)的精细结构分裂,进而拟合获得了原子nD里德堡态的量子亏损。通过分析里德堡原子nD态精细结构分裂的测量误差,去除了里德堡原子相互作用引起的能级频移,提高了里德堡nD态量子亏损测量的精确度。 展开更多
关键词 里德堡原子 量子亏损 电磁感应透明
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CsPbBr3量子点辅助结晶制备高效钙钛矿太阳能电池 被引量:2
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作者 李颖慧 刘钢 《湘潭大学学报(自然科学版)》 CAS 2024年第4期94-102,共9页
钙钛矿活性层是钙钛矿太阳电池中的重要组成部分,其成膜质量影响着钙钛矿太阳能电池的器件性能.该文介绍了一种晶体种子辅助钙钛矿薄膜结晶的方法,即在PbI2溶液中预先引入少量的CsPbBr3量子点作为种子晶体,诱导钙钛矿的自下而上结晶,促... 钙钛矿活性层是钙钛矿太阳电池中的重要组成部分,其成膜质量影响着钙钛矿太阳能电池的器件性能.该文介绍了一种晶体种子辅助钙钛矿薄膜结晶的方法,即在PbI2溶液中预先引入少量的CsPbBr3量子点作为种子晶体,诱导钙钛矿的自下而上结晶,促使形成高质量的钙钛矿薄膜.扫描电子显微镜结果显示,CsPbBr3量子点引入后,钙钛矿薄膜形貌明显改善,晶粒增大、薄膜针孔消失,这表明了CsPbBr3量子点作为种子晶体能够促进钙钛矿薄膜晶粒生长,改善钙钛矿薄膜形貌.高质量的钙钛矿薄膜有助于减少钙钛矿晶界,提升光吸收性能,抑制光生载流子复合,进而提升器件的光电转换性能.最后,将改进后的钙钛矿薄膜组装成太阳能电池,其最佳光电转换效率为20.64%,相应的开路电压为1.08 V、短路电流为24.0 mA·cm^(-2)、填充因子为79.64%. 展开更多
关键词 CsPbBr3量子点 辅助结晶 晶界缺陷 钙钛矿太阳能电池
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单层1T-VS_(2)的电子结构和量子电容性质研究
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作者 李雯婷 王维华 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期73-78,共6页
以石墨烯为代表的低维材料由于费米能级附近有限的态密度,导致量子电容较低,限制了其作为电极材料的超级电容器双电层电容的提升.采用基于密度泛函理论的第一性原理计算方法,以1T-VS_(2)为例,研究具有类石墨烯结构的准二维材料的量子电... 以石墨烯为代表的低维材料由于费米能级附近有限的态密度,导致量子电容较低,限制了其作为电极材料的超级电容器双电层电容的提升.采用基于密度泛函理论的第一性原理计算方法,以1T-VS_(2)为例,研究具有类石墨烯结构的准二维材料的量子电容的微观机理及其性能调控.研究结果表明,铁磁性的本征和含V空位缺陷的1T-VS_(2)在零偏压处的量子电容为~300μF/cm^(2),远高于石墨烯.此外,含有V空位缺陷体系在负偏压区的高量子电容区间更加扩展,可以匹配更宽工作电压窗口的电解质材料,有利于提高能量密度. 展开更多
关键词 1T-VS_(2) 电子结构 量子电容 本征缺陷 第一性原理计算
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晶格工程电子态调控研究
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作者 张丹彤 薛冬峰 《量子电子学报》 CAS CSCD 北大核心 2024年第6期839-851,共13页
晶格工程在材料科学和器件设计领域扮演着关键角色,通过精确构建晶格有序态、超晶格态、晶格缺陷态等,能够有效构筑材料的拓扑有序态,实现宏观尺度晶格架构定制并提升其在光、电、磁等领域的性能。基于晶格的本征周期性形成的拓扑有序... 晶格工程在材料科学和器件设计领域扮演着关键角色,通过精确构建晶格有序态、超晶格态、晶格缺陷态等,能够有效构筑材料的拓扑有序态,实现宏观尺度晶格架构定制并提升其在光、电、磁等领域的性能。基于晶格的本征周期性形成的拓扑有序态材料,其特殊的能带结构在电子输运过程中表现出高导电性、较低的能量损耗以及特殊的量子霍尔效应;基于超晶格的空间组装性和纵向旋转性构筑的摩尔条纹系列材料,为光电传感器和光子学器件等性能的提升开辟了新途径;而晶格缺陷能够有效构筑局域电子态、缺陷自旋态等特殊效应,有利于设计磁性调控和磁存储器件。 展开更多
关键词 量子光学 晶格工程 晶格缺陷 超晶格 晶格应变
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Energy levels of 1s^2n d(n≤9)states for lithium-like ions 被引量:3
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作者 胡木宏 王治文 +2 位作者 曾凡伟 王涛 王晶 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期169-175,共7页
The full-core plus correlation method with multi-configuration interaction wave functions is extended to the calcu- lation of the non-relativistic energies of ls2nd (n ≤9) states for the lithium isoelectronic seque... The full-core plus correlation method with multi-configuration interaction wave functions is extended to the calcu- lation of the non-relativistic energies of ls2nd (n ≤9) states for the lithium isoelectronic sequence from Z = 11 to 20. Relativistic and mass-polarization effects on the energy are calculated as the first-order perturbation correction. The quantum-electrodynamics correction is also included. The fine structure splittings are determined from the expectation values of spin-orbit and spin-other-orbit interaction operators in the Pauli-Breit approximation. Combining the term energies of lowly excited states obtained with the quantum defects calculated by the single channel quantum defect theory, each of which is a smooth function of energy and approximated by a weakly varying function of energy, the ion potentials of highly excited states (n ≥ 6) are obtained with the semi-empirical iteration method. The results are compared with experimental data in the literature and found to be closely consistent with the regularity. 展开更多
关键词 lithium-like ions excited states quantum defect theory quantum defect
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喷墨打印用高稳定性水系ZnSe:Mn量子点的制备及光学性能研究
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作者 敬新柯 胡晓博 +2 位作者 王建成 王蒙蒙 曾赛 《广州化工》 CAS 2024年第15期20-24,31,共6页
水系锰离子掺杂硒化锌(ZnSe:Mn)量子点因其可大规模合成、环境友好无毒性而受到研究者们的广泛关注。然而,表面缺陷多易引起晶体氧化分解、纳米晶体自净化效应导致离子掺杂困难等问题,极大地降低了ZnSe:Mn量子点的荧光性能及其稳定性,... 水系锰离子掺杂硒化锌(ZnSe:Mn)量子点因其可大规模合成、环境友好无毒性而受到研究者们的广泛关注。然而,表面缺陷多易引起晶体氧化分解、纳米晶体自净化效应导致离子掺杂困难等问题,极大地降低了ZnSe:Mn量子点的荧光性能及其稳定性,并限制其实际应用。本文利用合适比例的异丙醇/水混合溶液和稀氢氧化钠溶液,通过“整体防御”结合“局部修复”的两步法改性策略对ZnSe:Mn量子点表面进行后处理,得到表面改性后的ZnSe:Mn量子点,并进行X射线衍射、X射线光电子能谱、荧光光谱、电子自旋共振波谱仪等测试表征。结果表明:该后处理技术可以简便高效地钝化ZnSe:Mn量子点的表面缺陷,大幅提高绝对量子产率至25%,并同时其稳定性得到显著提升,有效抑制了晶格的氧化解离过程,这为制备高性能的水溶性ZnSe:Mn量子点提供了可行途径。通过配制水性量子点墨水并进行喷墨打印演示,证明该材料有望作为一种可应用于塑料外观的新型品牌标记方式。 展开更多
关键词 ZnSe:Mn量子点 表面改性 缺陷钝化 荧光性能 喷墨打印
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Theoretical study on 2s2p^6np Rydberg states of Cu^(19+)ion
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作者 Zhang Zhen-Rong Cheng Xin-Lu +2 位作者 Liu Zi-Jiang Yang Jian-Hui Li Hui-Fang 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期153-157,共5页
We report on the calculations of transition wavelengths and weighted oscillator strengths for 2s22p^6 2s2p^6np (4 〈 n 〈 20) electric dipole (El) transitions of Cu^19+ ion. The flexible atomic code (FAC) has b... We report on the calculations of transition wavelengths and weighted oscillator strengths for 2s22p^6 2s2p^6np (4 〈 n 〈 20) electric dipole (El) transitions of Cu^19+ ion. The flexible atomic code (FAC) has been adopted for the calculations. Comparisons are made with the experimental data available, showing that the present results for 4 〈 n 〈 6 are more accurate than the previous calculated values. Furthermore, combining the quantum defect theory (QDT) with the transition energies of 2s^22p^62s2p^6np, the quantum defects for 2s2p^6np Rydberg series of Cu^19+ ion are determined. In addition, the energies of any highly excited states (n 〉 20) for this series can be reliably predicted using the QDT and the given quantum defects. The ionization energies for Cu^19+ and Cu^20+ ions are also calculated and they excellently accord with previous experimental and calculated values. 展开更多
关键词 Cu^19+ion transition wavelength quantum defect quantum defect theory
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光纤激光模式不稳定研究十年回顾与展望 被引量:8
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作者 王建军 刘玙 +7 位作者 李敏 冯曦 楚秋慧 张春 高聪 陶汝茂 林宏奂 景峰 《强激光与粒子束》 EI CAS CSCD 北大核心 2020年第12期43-54,共12页
2010年模式不稳定现象首次报道,开启了光纤激光与废热的斗争史。回顾了10年来模式不稳定现象的研究进展,概述了光纤激光模式不稳定物理表征、基本原理、理论研究、影响因素和抑制策略等,介绍了高功率光纤激光在模式不稳定抑制方面取得... 2010年模式不稳定现象首次报道,开启了光纤激光与废热的斗争史。回顾了10年来模式不稳定现象的研究进展,概述了光纤激光模式不稳定物理表征、基本原理、理论研究、影响因素和抑制策略等,介绍了高功率光纤激光在模式不稳定抑制方面取得的最新成果,展望了高功率光纤激光模式不稳定研究的未来发展,对光纤激光模式不稳定未来可能的研究方向进行了展望。 展开更多
关键词 模式不稳定 光纤激光 热效应 量子亏损 增益饱和
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