Physica E-low-dimensional Systems & Nanostructures最新文献_第8页

Broken sublattice symmetry induced gap opening of spin-polarized Dirac cone in MnF3 亚晶格对称性破缺诱导MnF3中自旋极化Dirac锥的隙开

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-29 DOI: 10.1016/j.physe.2025.116382

Limei Zheng, Yu Li, Dazhi Sun, Baozeng Zhou, Xiaocha Wang

Two-dimensional (2D) transition-metal trihalides have received extensive attention in the field of novel spintronic devices and heterostructure coupling is an effective method for achieving multifunctional integration and regulation. In this work, using first-principles calculations, we systematically study the electronic structure and magnetic properties of the 2D MnF₃/graphene heterostructures. MnF₃ monolayer exhibits Dirac half-metal properties, with electron states featuring Dirac cones in its single spin channel. With different stacking configurations, the electronic properties of both are well preserved from the band structure, interfacial charge transfer only causes the relative movement of the electronic states. Additionally, due to the broken sublattice symmetry of MnF₃ in heterostructure, a gap opening of 24.9 meV appears around the spin-polarized Dirac cone in MnF₃. Moreover, the formation of heterostructure significantly enhances the in-plane magnetic anisotropy of the MnF₃ monolayer. By reducing the interlayer distance, the spin-polarized Dirac cone has a larger gap opening of 555.5 meV, which induces the transition of MnF₃ from Dirac half-metal to magnetic semiconductor, and the Curie temperature (T_C) increases obviously. Furthermore, a spin logic device based on MnF₃/graphene heterostructures is proposed, which can complete the resistive state switching from the "1″ state to the "0″ state by application of pressure. These results provide a reference for the application of MnF₃/graphene heterostructure in spintronic devices.

二维过渡金属三卤化物在新型自旋电子器件领域受到广泛关注，异质结构耦合是实现多功能集成和调控的有效方法。在这项工作中，我们使用第一性原理计算，系统地研究了二维MnF3/石墨烯异质结构的电子结构和磁性能。MnF3单层膜具有狄拉克半金属性质，其单自旋通道的电子态具有狄拉克锥。在不同的堆叠构型下，从能带结构上看，两者的电子性质都得到了很好的保留，界面电荷转移只引起电子态的相对运动。此外，由于MnF3异质结构中亚晶格对称性的破坏，在MnF3中自旋极化的Dirac锥周围出现了24.9 meV的隙开。此外，异质结构的形成显著增强了MnF3单层的面内磁各向异性。通过减小层间距离，自旋极化的Dirac锥隙开度增大至555.5 meV，诱导MnF3从Dirac半金属向磁性半导体转变，居里温度（TC）明显升高。此外，提出了一种基于MnF3/石墨烯异质结构的自旋逻辑器件，该器件可以通过施加压力完成从“1″”状态到“0″”状态的电阻性状态切换。这些结果为MnF3/石墨烯异质结构在自旋电子器件中的应用提供了参考。

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引用次数: 0

Optical photonic diode realization through spatial self-phase modulation using Mn3O4 nanoparticles 利用Mn3O4纳米粒子空间自相位调制实现光学光子二极管

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-25 DOI: 10.1016/j.physe.2025.116378

K.V. Jayaprasad, Titu Thomas, Manu Vaishakh, Sheenu Thomas

The growing demand for efficient nonlinear optical (NLO) materials for photonic devices such as isolators, switches, and telecommunication components necessitates the exploration of new nanostructured systems. Transition metal oxides like Mn₃O₄, with strong electronic interactions and thermal responses, remain relatively underexplored for their NLO behavior. In this work, Mn₃O₄ nanoparticles synthesized via ultrasonication-assisted precipitation were investigated using spatial self-phase modulation (SSPM) with a 532 nm CW DPSS laser. Structural and morphological characteristics were confirmed by XRD and TEM analyses. Nonlinear optical parameters, including the nonlinear refractive index (n₂) and thermo-optic coefficient

\frac{dn}{d T}

, were determined from the variation of SSPM patterns with laser intensity. Furthermore, a photonic diode based on a cascaded Mn₃O₄/TiO₂ hybrid structure was demonstrated, enabling nonreciprocal light propagation through unidirectional SSPM excitation. These findings highlight Mn₃O₄ nanoparticles as promising candidates for NLO applications, while the proposed hybrid photonic diode offers potential in integrated optics, optical switching, and telecommunication technologies.

由于隔离器、开关和电信元件等光子器件对高效非线性光学（NLO）材料的需求不断增长，因此有必要探索新的纳米结构系统。像Mn3O4这样具有强电子相互作用和热响应的过渡金属氧化物，其NLO行为的研究相对较少。本文采用空间自相位调制（SSPM）技术，利用532 nm连续波DPSS激光器对超声辅助沉淀法制备纳米Mn3O4进行了研究。通过XRD和TEM分析证实了材料的结构和形态特征。非线性光学参数包括非线性折射率（n2）和热光系数dndT随激光强度的变化。此外，基于级联Mn3O4/TiO2杂化结构的光子二极管被证明，使光通过单向SSPM激发非互反传播。这些发现强调了Mn3O4纳米颗粒是NLO应用的有希望的候选者，而所提出的混合光子二极管在集成光学、光开关和电信技术方面具有潜力。

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引用次数: 0

Klein tunneling and Fabry–Pérot resonances in twisted bilayer graphene 扭曲双层石墨烯中的克莱因隧穿和法布里-帕姆罗共振

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-23 DOI: 10.1016/j.physe.2025.116379

A. Bahlaoui , Y. Zahidi

The paper discusses the Klein tunneling and Fabry–Pérot resonances of charge carriers through a rectangular potential barrier in twisted bilayer graphene. Within the framework of the low-energy excitations, the transmission probability and the conductance are obtained depending on the parameters of the problem. Owing to the moiré-induced anisotropy of the Hamiltonian in twisted bilayer graphene, the propagation of charge carriers exhibits an anisotropic behavior in Klein tunneling and Fabry–Pérot resonances. Moreover, we show that the anisotropy of the charge carriers induces asymmetry and deflection in the Fabry–Pérot resonances and Klein tunneling, and they are extremely sensitive to the height of the potential applied. Additionally, we found that the conductance is strongly sensitive to the barrier height but weakly sensitive to the barrier width. Therefore, it is possible to control the maxima and minima of the conductance of charge carriers in twisted bilayer graphene. With our results, we gain an in-depth understanding of tunneling properties in twisted bilayer graphene, which may help in the development and design of novel electronic nanodevices based on anisotropic 2D materials.

本文讨论了电荷载流子在扭曲双层石墨烯中穿过矩形势垒时的克莱因隧穿和法布里-潘氏共振。在低能激励的框架下，根据问题的参数，得到了传输概率和电导。由于在扭曲双层石墨烯中莫伊莫尔变诱发了哈密顿量的各向异性，载流子在克莱因隧穿和法布里-普氏变共振中表现出各向异性行为。此外，我们还发现载流子的各向异性引起了法布里-帕姆罗共振和克莱因隧穿的不对称和偏转，并且它们对所施加的电位高度极为敏感。此外，我们发现电导对势垒高度敏感，而对势垒宽度敏感。因此，可以控制扭曲双层石墨烯中载流子电导率的最大值和最小值。通过我们的研究结果，我们深入了解了扭曲双层石墨烯的隧道特性，这可能有助于基于各向异性二维材料的新型电子纳米器件的开发和设计。

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引用次数: 0

Temperature-dependent photoluminescence from nanostructured silicon: role of quantum-confined Bloch states and interfacial defects 纳米结构硅的温度依赖性光致发光：量子受限布洛赫态和界面缺陷的作用

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-23 DOI: 10.1016/j.physe.2025.116380

Shayari Basu , Ujjwal Ghanta , Saddam Khan , Manotosh Pramanik , Rajalingam Thangavel , Bipul pal , Syed Minhaz Hossain

The strong visible photoluminescence (PL) in surface-oxidized nanostructured silicon emerges from the interplay between intrinsic Bloch states and oxide-related interfacial defects, making it difficult to isolate their role. Temperature-dependent

(5 - 350 K)

PL measurements on nanostructured silicon with varying crystallite sizes manifest three distinct decay mechanisms involving band-to-band, band-to-trap and trap-to-trap transitions to multiple emission bands appearing in the convoluted broad PL spectrum. At lower temperatures

(≲ 225 K)

, PL peak energy associated with the quantum-confined Bloch states exhibits a nearly linear blue shift, governed by a strong inverse power law dependence of the temperature coefficient on the effective crystallite size, while this trend reverses at higher temperatures. Conversely, the defect-related peak energies increase monotonically at a nearly constant rate throughout the experimental temperature range. A general analytical model for finite systems with a separable pseudo-potential effectively estimates the contributions from different decay channels to the PL emission. Theoretical results align well with the experimentally obtained values of the power-law exponents, offering a novel way to distinguish between the radiative recombination channels involving quantum-confined Bloch states and interfacial defects/trap states in nanostructured silicon.

表面氧化纳米结构硅的强可见光致发光（PL）是由内部Bloch态和氧化相关界面缺陷的相互作用产生的，这使得它们的作用很难分离出来。在不同晶粒尺寸的纳米结构硅上的温度依赖（5−350K） PL测量显示出三种不同的衰变机制，包括带到带、带到陷阱和陷阱到陷阱的转变，到多个发射带出现在复杂的宽PL光谱中。在较低的温度< 225K时，与量子受限布洛赫态相关的PL峰值能量表现出近似线性的蓝移，这是由温度系数与有效晶粒尺寸之间强烈的逆幂律关系所控制的，而在较高的温度下，这一趋势正好相反。相反，缺陷相关的峰值能量在整个实验温度范围内以几乎恒定的速率单调增加。具有可分离伪势的有限系统的一般解析模型有效地估计了不同衰减通道对PL发射的贡献。理论结果与实验得到的幂律指数值吻合良好，为区分纳米结构硅中涉及量子受限布洛赫态和界面缺陷/陷阱态的辐射复合通道提供了一种新的方法。

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引用次数: 0

Adsorption of toxic gases chlorine, phosgene, and mustard on tetrahexcarbon: DFT and semi-empirical MD studies 有毒气体氯、光气和芥菜在四己碳上的吸附：DFT和半经验MD研究

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-20 DOI: 10.1016/j.physe.2025.116376

Morteza Torabi Rad, Ramin Karimian

This study demonstrates that tetrahexcarbon (THC) serves as an effective substrate for detecting toxic gases chlorine, phosgene, and mustard through non-covalent interactions. Density functional theory (DFT) calculations reveal excellent agreement with reference structures and size-dependent morphology (planar C₆₀H₂₈ vs. saddle-shaped C₉₈H₃₆). The THC substrate maintains a 3.83 eV band gap with

<

12 % reduction upon adsorption, while DOS, NBO, and ELF analyses confirm physisorption with minimal electronic perturbation. Adsorption energies follow reasonable pattern: mustard (-24.75 kcal mol^-1)

>

phosgene (-13.18 kcal mol^-1)

>

chlorine (-10.56 kcal mol^-1), supported by QTAIM showing 2-11 bond critical points with positive

\nabla^{2} ρ

. Chlorine exhibits superior sensitivity (9.11 × 10¹⁸ electrons/m³) and fast recovery (1.84 ns), enabling reusable detection, while mustard’s slow recovery (46.1 s) suggests single-use applications. Thermodynamics confirm spontaneous adsorption (

Δ G < 0

) with entropy trends reflecting molecular complexity, consistent with water interactions. Semi-empirical molecular dynamics (MD) simulations confirm the DFT-optimized configuration as the global minimum, with all sampled states showing higher energies and no chemical reactions, further validating THC’s physisorption capability for these toxic gases. These results position THC as a versatile platform for both real-time monitoring and one-time detection of chemical threats. Future work will investigate doping techniques to further optimize the properties of THC for applications in sensing, adsorption, and catalysis.

该研究表明，四己碳（THC）通过非共价相互作用作为检测有毒气体氯、光气和芥菜的有效底物。密度泛函理论（DFT）的计算结果与参考结构和尺寸相关的形貌（平面C60H28和鞍形C98H36）非常吻合。THC底物在吸附后保持了3.83 eV的带隙，减少了12%，而DOS、NBO和ELF分析证实了在最小的电子扰动下的物理吸附。吸附能符合合理模式：芥子气（-24.75 kcal mol-1）；光气（-13.18 kcal mol-1）；氯（-10.56 kcal mol-1），由QTAIM支持，呈现2-11键临界点，且∇2ρ为正。氯表现出优越的灵敏度（9.11 × 1018电子/m3）和快速回收（1.84 ns），可以重复使用的检测，而芥末的缓慢回收（46.1 s）表明单次使用。热力学证实了自发吸附（ΔG<0），熵趋势反映了分子的复杂性，与水的相互作用一致。半经验分子动力学（MD）模拟证实了dft优化的构型是全局最小的，所有采样态都显示出更高的能量，没有化学反应，进一步验证了四氢大麻醇对这些有毒气体的物理吸附能力。这些结果使THC成为实时监测和一次性检测化学威胁的多功能平台。未来的工作将研究掺杂技术，以进一步优化四氢大麻酚在传感、吸附和催化方面的应用。

{"title":"Adsorption of toxic gases chlorine, phosgene, and mustard on tetrahexcarbon: DFT and semi-empirical MD studies","authors":"Morteza Torabi Rad, Ramin Karimian","doi":"10.1016/j.physe.2025.116376","DOIUrl":"10.1016/j.physe.2025.116376","url":null,"abstract":"<div><div>This study demonstrates that tetrahexcarbon (THC) serves as an effective substrate for detecting toxic gases chlorine, phosgene, and mustard through non-covalent interactions. Density functional theory (DFT) calculations reveal excellent agreement with reference structures and size-dependent morphology (planar C<sub>60</sub>H<sub>28</sub> vs. saddle-shaped C<sub>98</sub>H<sub>36</sub>). The THC substrate maintains a 3.83eV band gap with <span><math><mo><</mo></math></span>12% reduction upon adsorption, while DOS, NBO, and ELF analyses confirm physisorption with minimal electronic perturbation. Adsorption energies follow reasonable pattern: mustard (-24.75kcalmol<sup>-1</sup>) <span><math><mo>></mo></math></span> phosgene (-13.18kcalmol<sup>-1</sup>) <span><math><mo>></mo></math></span> chlorine (-10.56kcalmol<sup>-1</sup>), supported by QTAIM showing 2-11 bond critical points with positive <span><math><mrow><msup><mrow><mo>∇</mo></mrow><mrow><mn>2</mn></mrow></msup><mi>ρ</mi></mrow></math></span>. Chlorine exhibits superior sensitivity (9.11 × 10<sup>18</sup> electrons/m<sup>3</sup>) and fast recovery (1.84ns), enabling reusable detection, while mustard’s slow recovery (46.1s) suggests single-use applications. Thermodynamics confirm spontaneous adsorption (<span><math><mrow><mi>Δ</mi><mi>G</mi><mo><</mo><mn>0</mn></mrow></math></span>) with entropy trends reflecting molecular complexity, consistent with water interactions. Semi-empirical molecular dynamics (MD) simulations confirm the DFT-optimized configuration as the global minimum, with all sampled states showing higher energies and no chemical reactions, further validating THC’s physisorption capability for these toxic gases. These results position THC as a versatile platform for both real-time monitoring and one-time detection of chemical threats. Future work will investigate doping techniques to further optimize the properties of THC for applications in sensing, adsorption, and catalysis.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116376"},"PeriodicalIF":2.9,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unraveling Mn intercalation and diffusion in NbSe2 bilayers through DFTB simulations 通过DFTB模拟揭示Mn在NbSe2双层膜中的嵌入和扩散

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-18 DOI: 10.1016/j.physe.2025.116355

Bruno Ipaves , Raphael B. de Oliveira , Guilherme da Silva Lopes Fabris , Matthias Batzill , Douglas S. Galvão

Understanding transition metal atoms’ intercalation and diffusion behavior in two-dimensional (2D) materials is essential for optimizing their performance in emerging applications. In this study, we used density functional tight binding (DFTB) simulations to investigate the atomic-scale mechanisms of manganese (Mn) intercalation into NbSe

_{2}

bilayers. Our results show that Mn prefers intercalated and embedded positions rather than surface adsorption, as cohesive energy calculations indicate enhanced stability in these configurations. Nudged elastic band (NEB) calculations revealed an energy barrier of 0.68 eV for the migration of Mn into the interlayer, comparable to other substrates, suggesting accessible diffusion pathways. Molecular dynamics (MD) simulations further demonstrated an intercalation concentration-dependent behavior. Mn atoms initially adsorb on the surface and gradually diffuse inward, resulting in an effective intercalation at higher Mn densities before clustering effects emerge. These results provide helpful insights into the diffusion pathways and stability of Mn atoms within NbSe

_{2}

bilayers, consistent with experimental observations and offering a deeper understanding of heteroatom intercalation mechanisms in transition metal dichalcogenides.

了解过渡金属原子在二维（2D）材料中的嵌入和扩散行为对于优化其在新兴应用中的性能至关重要。在这项研究中，我们使用密度功能紧密结合（DFTB）模拟来研究锰（Mn）嵌入NbSe2双层结构的原子尺度机制。我们的研究结果表明，Mn更倾向于嵌入和嵌入的位置，而不是表面吸附，因为结合能计算表明这些构型的稳定性增强。微推弹性带（NEB）计算显示，Mn迁移到中间层的能量势垒为0.68 eV，与其他衬底相当，表明可以通过扩散途径。分子动力学（MD）模拟进一步证明了插层的浓度依赖行为。锰原子最初吸附在表面，逐渐向内扩散，导致在高锰密度下有效嵌入，然后才出现聚类效应。这些结果与实验观察结果一致，有助于深入了解NbSe2双层中Mn原子的扩散途径和稳定性，并对过渡金属二硫族化合物中的杂原子嵌入机制有了更深入的了解。

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引用次数: 0

Size and dielectric-dependent plasmonic resonances in CdS@Ag core–shell quantum dots: Field enhancement, dispersion, and slow-light effects 尺寸和介电相关的等离子共振在CdS@Ag核壳量子点：场增强，色散，和慢光效应

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-17 DOI: 10.1016/j.physe.2025.116371

Shewa Getachew Mamo

This study presents a comprehensive theoretical and numerical investigation of size- and host-medium dielectric-dependent plasmonic resonances in CdS@Ag core–shell quantum dots, with particular emphasis on field enhancement, optical dispersion, and slow-light effects. A hybrid framework combining the Maxwell–Garnett effective medium theory with a size-corrected electrostatic model was employed to compute the effective dielectric response and group velocity characteristics. The results reveal that local field enhancement is maximized by thicker Ag shells and low-permittivity hosts, enabling strong amplification of near-field intensities. Dual plasmon resonances, arising from the CdS/Ag and Ag/host interfaces, govern the field enhancement factor, refractive index and absorption spectra, producing tunable resonance shifts with variations in core radius, shell thickness, and host permittivity. Near these resonances, pronounced dispersion leads to a substantial increase in the group index, with group velocity reduced by more than an order of magnitude and, in certain regimes, reversed to negative values. Enhanced slow-light effects are particularly evident in high-permittivity hosts such as ZnO, where plasmon–exciton coupling further intensifies dispersion and suppresses pulse propagation. These findings provide new insights into the structural and dielectric control of plasmonic quantum dots and establish design guidelines for their application in optical delay lines, photonic modulators, sensors, and nonlinear optical devices.

本研究对CdS@Ag核壳量子点中与尺寸和宿主介质介电相关的等离子体共振进行了全面的理论和数值研究，特别强调了场增强、光色散和慢光效应。采用麦克斯韦-加内特有效介质理论和尺寸校正静电模型相结合的混合框架计算了有效介电响应和群速度特性。结果表明，较厚的银壳层和低介电常数的基体可以最大限度地增强局部场，从而实现近场强度的强放大。由CdS/Ag和Ag/宿主界面产生的双等离子体共振控制着场增强因子、折射率和吸收光谱，产生可调谐的共振位移，随核心半径、壳层厚度和宿主介电常数的变化而变化。在这些共振附近，明显的色散导致群指数大幅增加，群速度降低了一个数量级以上，在某些情况下，反而变为负值。增强的慢光效应在高介电常数的介质中尤其明显，如ZnO，其中等离子体-激子耦合进一步增强色散并抑制脉冲传播。这些发现为等离子体量子点的结构和介电控制提供了新的见解，并为其在光延迟线、光子调制器、传感器和非线性光学器件中的应用建立了设计指南。

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引用次数: 0

Efficient broadband solar absorber and thermal emitter based on Ti and InAs with pyramid-like structure 基于金字塔状结构Ti和InAs的高效宽带太阳能吸收体和热发射体

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-17 DOI: 10.1016/j.physe.2025.116377

Kang An , Mengsi Liu , Hua Yang , Zao Yi , Chaojun Tang , Juan Deng , Junqiao Wang , Boxun Li

This paper innovatively proposes a broadband solar absorber and thermal emitter with dual-function integration, achieving breakthroughs in the fields of photothermal conversion and high-temperature thermal emission through three core innovations. First, it integrates high-temperature-resistant metal titanium (Ti) and semiconductor indium arsenide (InAs) into a gradient-like pyramid structure for the first time—this design breaks the limitations of single-material systems (InAs has a narrow intrinsic absorption bandwidth, and pure Ti suffers from insufficient radiation stability). Second, a novel triple-resonance mechanism is developed to realize multi-scale light manipulation: Mie resonance at the pyramid apex enables high-efficiency absorption of ultraviolet-near-infrared (UV-NIR) light, Fabry-Perot cavities in the gaps trap mid-infrared light, and plasmonic-semiconductor coupling at the Ti/InAs interface achieves a 3–5-fold enhancement of the local electric field. Third, the symmetric structure ensures polarization independence and incident angle insensitivity, addressing the issue of performance degradation of traditional absorbers under oblique incidence. Finite Difference Time Domain (FDTD) simulations combined with preliminary experimental verification confirm the excellent performance of this design: the broadband average absorption rate in the 280–3000 nm range reaches 99.06 %, and the weighted average absorption efficiency under AM1.5 conditions is 99.02 % with a solar energy loss of only 0.98. It maintains high radiation efficiency at high temperatures: 97.15 % at 1000 K and 97.77 % at 1200 K (benefiting from the high-temperature stability of Ti (melting point: 1668 °C) and the enhanced high-temperature carrier excitation of InAs). Even when the incident angle increases from 0° to 60°, the weighted average absorption efficiency of transverse electric (TE) waves and transverse magnetic (TM) waves remains >91.05 %, outperforming similar symmetric structure. This study realizes the integration of ultra-broadband absorption, high-temperature stable emission, and angle/polarization insensitivity, providing a new paradigm for high-performance solar energy collection and photothermal conversion systems.

本文创新性地提出了一种双功能集成的宽带太阳能吸收器和热辐射器，通过三项核心创新，在光热转换和高温热辐射领域取得突破。首先，它首次将耐高温金属钛（Ti）和半导体砷化铟（InAs）集成到一个类似梯度的金字塔结构中，这一设计打破了单材料系统的局限性（InAs固有吸收带宽窄，纯Ti辐射稳定性不足）。其次，建立了一种新的三重共振机制来实现多尺度的光操纵：金字塔顶点的Mie共振可以高效吸收紫外-近红外（UV-NIR）光，间隙中的Fabry-Perot腔可以捕获中红外光，Ti/InAs界面的等离子体-半导体耦合可以实现3 - 5倍的局部电场增强。第三，对称结构保证了偏振无关性和入射角不敏感，解决了传统吸光器在斜入射下性能下降的问题。时域有限差分（FDTD）仿真结合初步实验验证证实了该设计的优异性能：280 ~ 3000 nm范围内的宽带平均吸收率达到99.06%,AM1.5条件下的加权平均吸收效率为99.02%，太阳能损失仅为0.98。它在高温下保持了很高的辐射效率：在1000 K时97.15%，在1200 K时97.77%（得益于Ti的高温稳定性（熔点：1668℃）和InAs的高温载流子激发增强）。当入射角从0°增加到60°时，横向电（TE）波和横向磁（TM）波的加权平均吸收效率仍保持91.05%，优于同类对称结构。该研究实现了超宽带吸收、高温稳定发射和角度/偏振不敏感的集成，为高性能太阳能收集和光热转换系统提供了新的范例。

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引用次数: 0

Theoretical design of Zr2B as a universal electrode for multivalent (Li, Na, K, Mg, Ca) ion batteries Zr2B作为多价（Li, Na， K, Mg, Ca）离子电池通用电极的理论设计

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-16 DOI: 10.1016/j.physe.2025.116375

Ming-Liang Qin , Cheng-Wei Lv , Yu-Pu He, Shao-Yi Wu, Qin-Sheng Zhu

Rechargeable metal-ion batteries demand advanced anode materials that simultaneously offer high storage capacity, rapid ion transport, and structural robustness. This study conducts first-principles computation using density functional theory (DFT) to systematically estimate the promising of a two-dimensional (2D) Zr₂B monolayer as an anode material for Li, Na, K, Mg and Ca-ion batteries (LIBs, NIBs, KIBs, MIBs and CIBs). The results indicate that Zr₂B exhibits outstanding mechanical integrity, thermal and kinetic stability, and metallic conductivity favorable for efficient electron transport. Remarkably, the migration barriers of alkali metal ions (Li, Na, and K) on the Zr₂B surface are exceptionally low. Particularly, Na presents a barrier of only 6 meV, remarkably smaller than the reported values for most MXenes. In addition, the open-circuit voltages (OCV) values for Li, Na, and K remain well-aligned with the ideal voltage window (0.1–1.0 V), enabling high energy density and mitigating dendrite risks. The results suggest that Zr₂B is a strong contender for use in advanced MXene-based anodes and provide valuable implications for future electrode development.

可充电金属离子电池需要先进的负极材料，同时提供高存储容量、快速离子传输和结构坚固性。本研究利用密度泛函理论（DFT）进行第一性原理计算，系统地估计了二维（2D） Zr2B单层作为Li， Na， K， Mg和ca离子电池（LIBs, NIBs, KIBs， MIBs和CIBs）阳极材料的前景。结果表明，Zr2B具有优异的机械完整性、热稳定性和动力学稳定性，以及有利于电子高效传递的金属导电性。值得注意的是，碱金属离子（Li， Na和K）在Zr2B表面的迁移障碍非常低。特别是，Na的势垒仅为6 meV，明显小于大多数MXenes的报道值。此外，Li、Na和K的开路电压（OCV）值与理想电压窗（0.1-1.0 V）保持良好对齐，从而实现高能量密度并减轻枝晶风险。结果表明，Zr2B是先进的mxene基阳极的有力竞争者，并为未来电极的发展提供了有价值的启示。

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引用次数: 0

Dielectric substrate dependence of thermoelectric transport in BLG-GaAs-BLG heterostructures BLG-GaAs-BLG异质结构中热电输运的介电衬底依赖性

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-16 DOI: 10.1016/j.physe.2025.116370

Vo Van Tai , Truong Van Tuan , Tran Trong Tai , Le Tri Dat , Nguyen Duy Vy

We theoretically study the thermoelectric transport

S

in a double-layer bilayer graphene (BLG-GaAs-BLG) system on dielectric substrates (h-BN, Al

_{2}

O

_{3}

, HfO

_{2}

). Electrons interact with GaAs acoustic phonons via both the deformation potential (acDP) and piezoelectric (acPE) scattering. Results show that piezoelectric scattering dominates the total transport, especially at low carrier density and high dielectric constant. Substrate dielectric constant significantly influences thermopower

S

, and the thermopower of the materials is in the order of HfO

_{2} >

Al

_{2}

O

_{3} >

h-BN. When densities on two BLG layers are unequal, the contribution from acDP scattering

S_{d}

decreases (increases) at low (high) densities versus equal densities, while acPE scattering

S_{g}

remains stable, making

S

largely

S_{g}

-dependent. Increasing interlayer distance

d

enhances

S

, while higher temperature boosts

S_{d}

(notably at low densities) with minimal effect on

S_{g}

. These insights and substrate-dependent trends demonstrate substrate engineering as a key parameter for optimizing BLG thermoelectric devices.

从理论上研究了介电衬底（h-BN, Al2O3, HfO2）上双层石墨烯（BLG-GaAs-BLG）体系的热电输运S。电子通过变形势（acDP）和压电（acPE）散射与砷化镓声子相互作用。结果表明，在低载流子密度和高介电常数条件下，压电散射在总输运中占主导地位。衬底介电常数显著影响热功率S，材料的热功率顺序为HfO2>； Al2O3> h-BN。当两个BLG层的密度不相等时，acDP散射对Sd的贡献在低（高）密度下比等密度下减小（增加），而acPE散射对Sg的贡献保持稳定，使得S在很大程度上依赖于Sg。增加层间距离d可以提高S，而温度升高可以提高Sd（特别是在低密度下），但对Sg的影响很小。这些见解和与衬底相关的趋势表明，衬底工程是优化BLG热电器件的关键参数。

{"title":"Dielectric substrate dependence of thermoelectric transport in BLG-GaAs-BLG heterostructures","authors":"Vo Van Tai , Truong Van Tuan , Tran Trong Tai , Le Tri Dat , Nguyen Duy Vy","doi":"10.1016/j.physe.2025.116370","DOIUrl":"10.1016/j.physe.2025.116370","url":null,"abstract":"<div><div>We theoretically study the thermoelectric transport <span><math><mi>S</mi></math></span> in a double-layer bilayer graphene (BLG-GaAs-BLG) system on dielectric substrates (h-BN, Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>, HfO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>). Electrons interact with GaAs acoustic phonons via both the deformation potential (acDP) and piezoelectric (acPE) scattering. Results show that piezoelectric scattering dominates the total transport, especially at low carrier density and high dielectric constant. Substrate dielectric constant significantly influences thermopower <span><math><mi>S</mi></math></span>, and the thermopower of the materials is in the order of HfO<span><math><mrow><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub><mo>></mo></mrow></math></span> Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><mrow><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub><mo>></mo></mrow></math></span> h-BN. When densities on two BLG layers are unequal, the contribution from acDP scattering <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>d</mi></mrow></msub></math></span> decreases (increases) at low (high) densities versus equal densities, while acPE scattering <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span> remains stable, making <span><math><mi>S</mi></math></span> largely <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span>-dependent. Increasing interlayer distance <span><math><mi>d</mi></math></span> enhances <span><math><mi>S</mi></math></span>, while higher temperature boosts <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>d</mi></mrow></msub></math></span> (notably at low densities) with minimal effect on <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span>. These insights and substrate-dependent trends demonstrate substrate engineering as a key parameter for optimizing BLG thermoelectric devices.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116370"},"PeriodicalIF":2.9,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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