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Bound state noise-like pulses generation from composite filtering effects 被引量:1
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作者 CHANG Qingyu ZHANG Caishi 《Optoelectronics Letters》 2025年第3期142-148,共7页
This paper demonstrated the generation of multi-wavelength bound state noise-like pulse(BNLP)in a dispersion-managed composite-filtered fiber laser consisting of nonlinear polarization rotation(NPR)and loop.In the cas... This paper demonstrated the generation of multi-wavelength bound state noise-like pulse(BNLP)in a dispersion-managed composite-filtered fiber laser consisting of nonlinear polarization rotation(NPR)and loop.In the case of BNLP,the generation is caused by the interaction between two noise-like pulses(NLPs)induced by the comb-filtering effect,and bound state level can be artificially controlled in the researches.Our work provides a new method for generating low-coherence pulses and establishes a research idea for the study of the comb-filtering effects. 展开更多
关键词 comb filtering effect nonlinear polarization composite filtering dispersion managed fiber laser bound state level low coherence pulses artificially controlled nonlinear polarization rotation
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Calculation of the fine structure of the level in Rydberg state of lithium 被引量:1
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作者 HUXian-quan XU Jie +1 位作者 MA Yong HENG Rui-lun 《原子与分子物理学报》 CAS CSCD 北大核心 2006年第B04期59-63,共5页
关键词 Rydberg态能量层 原子核极化 水平间隔 原子结构
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Fermi level pinning effects at gate–dielectric interfaces influenced by interface state densities 被引量:1
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作者 洪文婷 韩伟华 +2 位作者 吕奇峰 王昊 杨富华 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期443-447,共5页
The dependences of Fermi-level pinning on interface state densities for the metal-dielectric, ploycrystalline silicon-dielectric, and metal silicide-dielectric interfaces are investigated by calculating their effectiv... The dependences of Fermi-level pinning on interface state densities for the metal-dielectric, ploycrystalline silicon-dielectric, and metal silicide-dielectric interfaces are investigated by calculating their effective work functions and their pinning factors. The Fermi-level pinning factors and effective work functions of the metal-dielectric interface are observed to be more susceptible to the increasing interface state densities, differing significantly from that of the ploycrystalline silicon-dielectric interface and the metal silicide-dielectric interface. The calculation results indicate that metal silicide gates with high-temperature resistance and low resistivity are a more promising choice for the design of gate materials in metal-oxide semiconductor(MOS) technology. 展开更多
关键词 interface state density Fermi-level pinning MIS structure effective work function
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A novel quantum information hiding protocol based on entanglement swapping of high-level Bell states 被引量:2
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作者 徐淑奖 陈秀波 +2 位作者 王连海 钮心忻 杨义先 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期231-238,共8页
Using entanglement swapping of high-level Bell states, we first derive a covert layer between the secret message and the possible output results of the entanglement swapping between any two generalized Bell states, an... Using entanglement swapping of high-level Bell states, we first derive a covert layer between the secret message and the possible output results of the entanglement swapping between any two generalized Bell states, and then propose a novel high-efficiency quantum information hiding protocol based on the covert layer. In the proposed scheme, a covert channel can be built up under the cover of a high-level quantum secure direct communication (QSDC) channel for securely transmitting secret messages without consuming any auxiliary quantum state or any extra communication resource. It is shown that this protocol not only has a high embedding efficiency but also achieves a good imperceptibility as well as a high security. 展开更多
关键词 quantum information hiding quantum covert'channel entanglement swapping high-level Bell states
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Integrated importance measure for multi-state coherent systems of k level 被引量:2
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作者 Xibin Zhao Shubin Si +2 位作者 Hongyan Dui Zhiqiang Cai Shudong Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期1029-1037,共9页
To verify the effectiveness of the integrated importance measure (IIM) for multi-state coherent systems of k level, the definition and physical meaning of IIM are demonstrated. Then, the improvement potential and Δ... To verify the effectiveness of the integrated importance measure (IIM) for multi-state coherent systems of k level, the definition and physical meaning of IIM are demonstrated. Then, the improvement potential and Δ-importance measures are generalized to multi-state coherent systems based on the system performance level, and the relationships between IIM and traditional importance measures are discussed. The characteristics of IIM are demonstrated in both series and parallel systems. Also, an application to an oil transportation system is given. The comparison results show that: (i) IIM has some useful properties that are not possessed by traditional importance measures; (ii) IIM is effective in evaluating the component role in multi-state systems when the component reliability and the failure rate are simultaneously considered. 展开更多
关键词 multi-state coherent system system performance level integrated importance measure system reliability
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Interaction of a pair coherent state with a three-level Λ-type atom and generation of a modified Bessel-Gaussian state with a vortex structure
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作者 唐慧琴 李绍新 +2 位作者 唐英 郑小娟 朱开成 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期115-119,共5页
The evolution of a system state is derived based on the nonresonant interaction of a three-level "Λ" type atom with two cavity modes at a pair coherent state and two classic fields,and a cavity field state is analy... The evolution of a system state is derived based on the nonresonant interaction of a three-level "Λ" type atom with two cavity modes at a pair coherent state and two classic fields,and a cavity field state is analyzed in detail under conditional detecting.It is found that the quantized modified Bessel-Gaussian states as well as the superposition states consisting of the quantized vortex states with different weighted coefficients may be prepared through carefully preparing an initial atomic state and appropriately adjusting the interaction time.The scheme provides an additional choice to realize the two-mode quantized vortex state within the context of cavity quantum electrodynamics(QED). 展开更多
关键词 quantized vortex state three-level Λ-type atom cavity quantum electrodynamics(QED)
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Energy level formula for two moving charged particles with Coulomb coupling derived via the entangled state representations
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作者 孟祥国 王继锁 梁宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期264-268,共5页
This paper derives energy level formula for two moving charged particles with Coulomb coupling by making full use of two mutually conjugate entangled state representations. These newly introduced entangled state repre... This paper derives energy level formula for two moving charged particles with Coulomb coupling by making full use of two mutually conjugate entangled state representations. These newly introduced entangled state representations seem to provide a direct and convenient approach for solving certain dynamical problems for two-body systems. 展开更多
关键词 two-body dynamic problem entangled state representation energy level formula
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Level Statistics Crossover of Chiral Surface States in a Three-Dimensional Quantum Hall System
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作者 Rubah Kausar Chao Zheng Xin Wan 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期99-103,共5页
Recent experiments have demonstrated the realization of the three-dimensional quantum Hall effect in highly anisotropic crystalline materials, such as ZrTe|_5 and BaMnSb_2. Such a system supports chiral surface states... Recent experiments have demonstrated the realization of the three-dimensional quantum Hall effect in highly anisotropic crystalline materials, such as ZrTe|_5 and BaMnSb_2. Such a system supports chiral surface states in the presence of a strong magnetic field, which exhibit a one-dimensional metal-insulator crossover due to suppression of surface diffusion by disorder potential. We study the nontrivial surface states in a lattice model and find a wide crossover of the level-spacing distribution through a semi-Poisson distribution. We also discover a nonmonotonic evolution of the level statistics due to the disorder-induced mixture of surface and bulk states. 展开更多
关键词 level Statistics Crossover of Chiral Surface states in a Three-Dimensional Quantum Hall System QUANTUM
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Generation of entangled coherent states for two cavity modes via resonant interaction with a V-type three-level atom
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作者 郑仕标 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2143-2146,共4页
This paper proposes a scheme for the generation of entangled coherent states for two cavity modes. In the scheme a V-type three-level atom is sent through a two-mode cavity filled with a coherent field. After the atom... This paper proposes a scheme for the generation of entangled coherent states for two cavity modes. In the scheme a V-type three-level atom is sent through a two-mode cavity filled with a coherent field. After the atom cavity interaction and detection of the atomic state the cavity modes may evolve to a superposition of two-mode coherent states. As the scheme is based on resonant atom-cavity interaction, the required interaction time is short, which is important in view of the decoherence. Moreover, additional classical pulses are unnecessary before and after the atom-cavlty interaction. 展开更多
关键词 entangled coherent state resonant interaction V-type three-level atom
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Generation of four-photon entangled states based on interaction between a three-level atom and two bimodal cavities
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作者 ZHANG Dengyu TANG Shiqing WANG Xinwen XIE Lijun ZHAN Xiaogui CHEN Yinhua 《商丘师范学院学报》 CAS 2011年第6期24-27,共4页
A simple scheme is presented for generating four-photon entangled states with interaction between a three-level atom and two bimodal cavities.In the proposed protocol,the quantum information is encoded on Fock states ... A simple scheme is presented for generating four-photon entangled states with interaction between a three-level atom and two bimodal cavities.In the proposed protocol,the quantum information is encoded on Fock states of the cavity fields.The detection of the atom can collapse the cavity made/wave function to the desired state.The experimental feasibility of our proposal is also discussed. 展开更多
关键词 quantum information THREE-level ATOM BIMODAL cavity ENTANGLED state
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INTERDECADAL SEA LEVEL VARIATION AT THE JAPANESE COAST AND LARGE SCALE CLIMATE STATE
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作者 崔茂常 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1995年第4期303-309,共7页
Thirty years of monthly mean anomalies of sea level(SL) at 15 Japanese coastal stations, sea sur-face temperature (SST) and sea level pressure (SLP) in or over the northern Pacific were analyzed bycanonical correlatio... Thirty years of monthly mean anomalies of sea level(SL) at 15 Japanese coastal stations, sea sur-face temperature (SST) and sea level pressure (SLP) in or over the northern Pacific were analyzed bycanonical correlation analysis (CCA) to study the relationship between the interdecadal SL variationand large scale climate state. Given two time-varying fields this technique identifies the pair ofspacial patterns with optimally correlated time series.The results show that there are two important air-sea interactive processes in the extratropicalPacific region for the variation of the SL at the Japanese coast on interdecadal scale. One is theocean heating or cooling of the atmosphere over the Kuroshio extension region, which results in ahuge SLP anomalous vortex with planetary spacial scale big enough to change the global climate. An-other is the large Kuroshio meander phenomenon controlled by the large-scale wind-stress curls oneyear earlier in the adjacent region of the Hawaiian Islands. The first process 展开更多
关键词 INTERDECADAL variability sea level at the JAPANESE COAST large scale CLIMATE state
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国家级开发区的“区政合一”改革:意涵厘定与逻辑阐释
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作者 邹奕 《中国行政管理》 北大核心 2026年第1期133-144,共12页
我国的一系列国家级开发区陆续开展“区政合一”改革,旨在提升行政效能、推动区域经济协同发展。此种改革一方面要进行开发区管理机构同相关地方政府的组织整合,包括职权配置、部门设置、人员编制的整合,另一方面要进行开发区同相关行... 我国的一系列国家级开发区陆续开展“区政合一”改革,旨在提升行政效能、推动区域经济协同发展。此种改革一方面要进行开发区管理机构同相关地方政府的组织整合,包括职权配置、部门设置、人员编制的整合,另一方面要进行开发区同相关行政区的地域统合。“区政合一”改革不仅可以消解管理机构与相关地方政府的部门重叠等问题,也能够避免管理机构与其他地方行政组织的权责纠葛,并且通过重新配置行政资源提升行政效能。“区政合一”改革有待于在法律框架之内加以规范和完善,可以从主体、对象、内容等方面进行优化。 展开更多
关键词 国家级开发区 区政合一 行政效能 行政法治
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加味芍药甘草汤联合戊酸雌二醇片治疗轻度宫腔粘连对微炎症状态及性激素水平的影响观察
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作者 游志恒 于清茜 王慧霞 《中华中医药学刊》 北大核心 2026年第1期219-223,共5页
目的探究加味芍药甘草汤联合戊酸雌二醇片治疗轻度宫腔粘连(intrauterine adhesion,IUA)对患者微炎症状态及性激素水平的影响。方法选取轻度IUA患者92例为研究对象,按照随机数字法分为对照组和观察组,每组46例。对照组予以戊酸雌二醇片... 目的探究加味芍药甘草汤联合戊酸雌二醇片治疗轻度宫腔粘连(intrauterine adhesion,IUA)对患者微炎症状态及性激素水平的影响。方法选取轻度IUA患者92例为研究对象,按照随机数字法分为对照组和观察组,每组46例。对照组予以戊酸雌二醇片治疗,观察组在对照组基础上联合加味芍药甘草汤治疗。对比两组患者临床疗效、治疗前后中医证候积分、子宫检查指标(子宫内膜厚度、子宫内膜容积)、血流动力学指标[子宫内膜螺旋动脉阻力指数(resistance index,RI)、搏动指数(pulsatility index,PI)]以及基质金属蛋白酶(matrix metalloproteinase,MMP)-2、MMP-3、MMP-9、炎症因子[转化生长因子(transforming growth factor,TGF)-β1、肿瘤坏死因子(tumor necrosis factor,TNF)-α、白细胞介素(interleukin,IL)-6]、性激素[雌二醇(estradiol,E_(2))、促黄体生成素(luteinizing hormone,LH)]水平间差异。结果治疗后观察组总有效率高于对照组(P<0.05),两组各项中医证候积分及TGF-β1、TNF-α、IL-6、LH水平均降低,且观察组降幅均高于对照组(均P<0.05),两组子宫内膜厚度、子宫内膜容积、PI、RI及MMP-2、MMP-3、MMP-9、E_(2)、LH水平均升高,且观察组升幅均高于对照组(均P<0.05)。结论加味芍药甘草汤联合戊酸雌二醇片治疗轻度IUA,可有效改善患者临床症状、子宫形态及血流动力学指标,疗效确切,其作用机制与调控基质金属蛋白酶、炎症因子及性激素表达相关。 展开更多
关键词 宫腔粘连 轻度 芍药甘草汤 戊酸雌二醇 炎症状态 性激素水平
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Four-Level Decay Model of^6P_(7/2) Excited State of Eu^(2+) Ion in KMgF_3
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作者 Hai Quan SU, Xian Ming ZHANG, ChunYu ZANG, Chun Shan SHI( Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第2期175-178,共4页
A four-level decay model of ~6P_(7/2) excited state of Eu^(2+_ ion in KMgF_3: Eu^(2+) has been proposed. The decay profiles of the ~6P_(7/2) excited state of Eu^(2+) are two exponential and the physical implication o... A four-level decay model of ~6P_(7/2) excited state of Eu^(2+_ ion in KMgF_3: Eu^(2+) has been proposed. The decay profiles of the ~6P_(7/2) excited state of Eu^(2+) are two exponential and the physical implication of each term in the fit equation responsible for the model is interpreted. The data obtained spectroscopically are in good agreement with the fit results. 展开更多
关键词 Four-level decay model divalent europium ~6P_(7/2) excited state KMgF_3.
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国家审计信息化建设能促进国有企业创新吗——基于审计信息化专门机构设立的准自然实验
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作者 房巧玲 王子宸 《审计与经济研究》 北大核心 2026年第1期35-46,共12页
推动国有企业创新是建设创新型国家的重要内容。以2007—2022年A股地方国有上市公司为样本,以国家审计信息化专门机构设立为准自然实验,实证检验国家审计信息化建设对国有企业创新的影响。研究发现,审计信息化建设能够显著促进国有企业... 推动国有企业创新是建设创新型国家的重要内容。以2007—2022年A股地方国有上市公司为样本,以国家审计信息化专门机构设立为准自然实验,实证检验国家审计信息化建设对国有企业创新的影响。研究发现,审计信息化建设能够显著促进国有企业创新,缓解代理问题和提升风险承担水平是该促进效应的作用机制。上述效应在有政治关联、内部控制质量较低、高科技行业、行业竞争程度较高以及地区市场化程度较高的企业中更为凸显。国家审计信息化建设在促进国有企业创新的同时,能够进一步提升企业的全要素生产率。研究成果有利于深入理解我国国家审计信息化进程及其影响后果,并为国有企业创新影响因素的研究提供了新的证据。 展开更多
关键词 国家审计 信息化建设 国有企业创新水平 企业内部治理 全要素生产率
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Four-Parameter Scheme for Ground Level of Helium Atom
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作者 HU Xian-Quan XU Jie +1 位作者 MA Yong ZHENG Rui-Lun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期906-910,共5页
In this paper,the ground state wave function of four parameters is developed and expression of the ground state level is derived for the helium atom when the radial Schrodinger equation of the helium atom is solved. T... In this paper,the ground state wave function of four parameters is developed and expression of the ground state level is derived for the helium atom when the radial Schrodinger equation of the helium atom is solved. The ground energy is respectively computed by the optimized aJgorithms of Matlab 7.0 and the Monte Carlo methods. Furthermore, the ground state wave function is obtained. Compared with the experiment value and the value with the variation calculus in reference, the results of this paper show that in the four-parameter scheme, not only the calculations become more simplified and precise, but also the radial wave function of the helium atom meets the space symmetry automatically in ground state. 展开更多
关键词 helium atom ground state level variation calculus wave function
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乡村治理转型下村级组织的分类治理机制研究——基于一个省级“千万工程”示范村的调查
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作者 李城 尹金龙 《山西农业大学学报(社会科学版)》 2026年第1期130-140,共11页
在乡村治理转型的背景下,村级组织如何在体制刚性化与社会结构变化的双重结构下找到属于自己的制度性位置,其生成逻辑和调适机制亟待理论回应。现有研究多聚焦于基层政权中正式组织的实践逻辑和调适过程,忽视了在法律意义上被定义为自... 在乡村治理转型的背景下,村级组织如何在体制刚性化与社会结构变化的双重结构下找到属于自己的制度性位置,其生成逻辑和调适机制亟待理论回应。现有研究多聚焦于基层政权中正式组织的实践逻辑和调适过程,忽视了在法律意义上被定义为自治组织的村级组织是如何应对多元治理事物的实践机制,因此本文在简约治理的理论内涵基础上提出“分类治理”的分析框架,探讨村级组织的调适机制及其治理逻辑。研究发现:村级组织通过事物属性识别将村庄事物划分为三种类型,在资源优化配置和主体分工处理的基础上对其施行分类治理,党组织在乡村社会设立党支部为村级组织分类治理提供了组织基础,在党支部统合下,重点中心性事物以党委统合治理机制、常规行政性事物以程序执行治理机制、村庄内生性事物以关系嵌入治理机制实现分类治理,而分类治理的前提是制度赋权所预留的弹性空间,该空间使得村级治理主体能够保持主体性和灵活性。分类治理是中国乡村治理体制保持活力的基本逻辑,该治理逻辑超越了西方语境下的国家—社会二元分割、互相对立的实践样态,建构了一种具有中国特色的国家与社会互融共生、相濡以沫的治理新格局。 展开更多
关键词 乡村治理转型 村级组织 分类治理 国家—社会
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Generation of multi-atom cluster states via an unconventional geometric phase shift in cavity QED 被引量:2
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作者 金星日 张英俏 +1 位作者 张寿 金东泽 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1220-1224,共5页
This paper proposes two schemes to generate the multi-atom cluster states. The first scheme is based on the interaction of atoms with a highly detuned cavity mode and a classical field, the second scheme is based on t... This paper proposes two schemes to generate the multi-atom cluster states. The first scheme is based on the interaction of atoms with a highly detuned cavity mode and a classical field, the second scheme is based on the interaction of atoms with a cavity mode, strongly driven by a resonant classical field. 展开更多
关键词 cluster state three-level atom
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Origin of Luminescent Centers and Edge States in Low-Dimensional Lead Halide Perovskites:Controversies,Challenges and Instructive Approaches 被引量:3
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作者 Jiming Bao Viktor G.Hadjiev 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第2期109-126,共18页
With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made ... With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made them appealing materials for high-efficiency,low-cost,solar cells and light-emitting devices.As such,recent observations of apparently deep-level and highly luminescent states in low-dimensional perovskites have attracted enormous attention as well as intensive debates.The observed green emission in 2D CsPb2Br5 and 0 D Cs4PbBr6 poses an enigma over whether it is originated from intrinsic point defects or simply from highly luminescent CsPbBr3 nanocrystals embedded in the otherwise transparent wide band gap semiconductors.The nature of deep-level edge emission in 2D Ruddlesden–Popper perovskites is also not well understood.In this mini review,the experimental evidences that support the opposing interpretations are analyzed,and challenges and root causes forthe controversy are discussed.Shortcomings in the current density functional theory approaches to modeling of properties and intrinsic point defects in lead halide perovskites are also noted.Selected experimental approaches are suggested to better correlate property with structure of a material and help resolve the controversies.Understanding and identification of the origin of luminescent centers will help design and engineer perovskites for wide device applications. 展开更多
关键词 LOW-DIMENSIONAL perovskites LUMINESCENT CENTERS Edge stateS Cesium LEAD halides Deep-level stateS Ruddlesden–Popper perovskites
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