Materials Today Physics最新文献_第4页

Defect formation energy of impurities in 2D materials: How does data engineering shape machine learning model selection? 二维材料中杂质的缺陷形成能量：数据工程如何塑造机器学习模型选择？

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-13 DOI: 10.1016/j.mtphys.2025.102006

A. El Alouani, M. Al Khalfioui, A. Michon, S. Vézian, P. Boucaud, M.T. Dau

Regressive Machine learning (ML) has emerged as an alternative method for theoretically evaluating materials properties. Most of ML-based study of materials properties including dataset handling, feature spaces, transformers and estimators have been reported without questioning the ML foundation of these components and their interactions with the outcomes because of the availability of homogeneous datasets, standardized training conditions and technical implementation challenges. In this paper, a database of defect impurities in 2D materials was used to assess the impact of ML workflow’s components on the training-inference process. By investigating descriptor engineering (vectorized matrix properties) and model algorithms (statistical tree-based and artificial neural network - ANN models) on two sub-datasets derived from the database (interstitial-int and adsorbate-ads impurities), we report a comprehensive study of the ML-based prediction of the energy formation of the impurities in 2D materials. Quantitatively, for the statistical models, the training errors lower than 1.4 eV and 1.1 eV were found thanks to the descriptor engineering for the int and the ads datasets, respectively. Regarding the ANN models, these values are 2.1 eV and 1.3 eV. The prediction errors on the unseen data (test sets) were found lower than the ones obtained without descriptor engineering for all models. However, the overfitting effect remains visible but less pronounced for the ads dataset than for the int dataset. This finding reveals the impact of the dataset characteristics on the performance of the ML ecosystem involving data engineering and model algorithms. Beyond the search of best performances in regressive ML prediction of 2D materials properties, our work demonstrates a full-scale study of the ML process starting from the data engineering to model evaluation and selection, allowing to benchmark the criteria for further ML assessment in terms of training, models and prediction. Our results could be reference for further works in ML-led prediction physics of materials science.

回归机器学习（ML）已经成为一种从理论上评估材料特性的替代方法。大多数基于机器学习的材料特性研究，包括数据集处理、特征空间、变压器和估计器，都是在没有质疑这些组件的机器学习基础及其与结果的相互作用的情况下进行的，因为同质数据集的可用性、标准化的训练条件和技术实现的挑战。本文利用二维材料中的缺陷杂质数据库来评估机器学习工作流的组件对训练-推理过程的影响。通过研究描述子工程（矢量化矩阵性质）和模型算法（基于统计树和人工神经网络- ANN模型），我们报告了基于ml的二维材料中杂质能量形成预测的全面研究。定量地，对于统计模型，由于对int和ads数据集的描述符工程，分别发现了低于1.4 eV和1.1 eV的训练误差。对于人工神经网络模型，这些值分别为2.1 eV和1.3 eV。发现所有模型在未见数据（测试集）上的预测误差低于未经描述符工程的预测误差。然而，与int数据集相比，广告数据集的过拟合效应仍然明显，但不那么明显。这一发现揭示了数据集特征对涉及数据工程和模型算法的机器学习生态系统性能的影响。除了在二维材料属性的回归机器学习预测中寻找最佳性能之外，我们的工作展示了从数据工程到模型评估和选择的机器学习过程的全面研究，允许在训练，模型和预测方面对进一步的机器学习评估标准进行基准测试。我们的研究结果可为进一步开展机器学习主导的材料科学预测物理工作提供参考。

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引用次数: 0

Enhanced broadband infrared radiative cooling of CeO2/PDMS coating via partial substitution of Ce with Nd 用Nd部分取代Ce增强CeO2/PDMS涂层的宽带红外辐射冷却

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-13 DOI: 10.1016/j.mtphys.2026.102017

Yu Duan , Mingrui Liu , Xianfeng Ye , Yu Liang , Danqi He , Zhijie Wei , Wanting Zhu , Yu Zhang , Wenyu Zhao , Qingjie Zhang

The development of high-performance infrared emissive materials is crucial for advancing energy utilization and thermal management technologies. To this end, we designed a series of Nd-doped CeO₂ materials with different dopant concentrations to precisely modulate oxygen vacancy concentration and impurity incorporation. The introduction of Nd not only facilitates the dynamic transition between Ce³⁺ and Ce⁴⁺ but also generates abundant oxygen vacancies and induces significant lattice distortion. These synergistic effects collectively narrow the electronic bandgap, facilitate carrier transitions, and reduce vibrational symmetry, thereby enhancing phonon-infrared interactions. As a result, Ce-Nd07 nanoparticles achieved a broadband emissivity of 0.923 (2.5–15 μm), which further increased to 0.935 when the material was fabricated into Ce-Nd07@PDMS composite coating. Furthermore, simulated radiative cooling tests reveal a temperature drop of 8.3 °C with a cooling efficiency of 12.3 %, confirming the exceptional radiative heat-dissipation capability. Additionally, the composite coating exhibits excellent UV resistance and hydrophobicity. These findings highlight a dual electronic-lattice engineering strategy for the development of next-generation radiative cooling materials.

高性能红外发射材料的发展对于推进能源利用和热管理技术至关重要。为此，我们设计了一系列不同掺杂浓度的nd掺杂CeO2材料，以精确调节氧空位浓度和杂质掺入。Nd的引入不仅促进了Ce3+和Ce4+之间的动态转变，而且产生了丰富的氧空位，引起了显著的晶格畸变。这些协同效应共同缩小了电子带隙，促进了载流子跃迁，降低了振动对称性，从而增强了声子-红外相互作用。结果表明，Ce-Nd07纳米粒子的宽带发射率为0.923 (2.5 ~ 15 μm)，制成Ce-Nd07@PDMS复合涂层后，该材料的宽带发射率进一步提高到0.935。此外，模拟辐射冷却试验表明，温度下降8.3°C，冷却效率为12.3%，证实了卓越的辐射散热能力。此外，复合涂层具有优异的抗紫外线和疏水性。这些发现强调了开发下一代辐射冷却材料的双电子晶格工程策略。

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引用次数: 0

Unveiling the governing factors of phonon transport across monolayer WS2 and WSe2 interfaces 揭示声子跨单层WS2和WSe2界面输运的控制因素

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-12 DOI: 10.1016/j.mtphys.2026.102016

Yijie Chen , Chunwei Zhang , Tong Wang , Guojun Li , Jiahui Lou , Qun Cao , Cheng Shao , Hongkun Li , Weidong Zheng

The group VI transition metal dichalcogenides (MoX₂ and WX₂, X = chalcogen) have attracted considerable interest for next-generation electronic devices owing to their unique physical properties. Although thermal transport across MoX₂ interfaces has been extensively investigated over the past decade, research on WX₂ interfaces remains limited, and large discrepancies in previous reports obscure the underlying mechanisms. In this work, we experimentally unveil the governing factors and the underlying mechanisms of phonon transport across WX₂ interfaces through measuring interfacial thermal conductance (G) of metal/WS₂(or WSe₂)/Al₂O₃ over the temperature (T) of 80–600 K using time-domain thermoreflectance (TDTR). We find that even for WS₂ grown by chemical vapor deposition, G of metal/WS₂/Al₂O₃ spreads in a wide range of 6.4–13.4 MW m⁻² K⁻¹ under room temperature. Through a detailed analysis of picosecond acoustic signals and a comparison of samples prepared under differing conditions, we experimentally demonstrate that the interfacial bonding strength, rather than the mismatch in phonon density of states, plays a decisive role in tuning G of WX₂ interfaces. Moreover, we observe that G of Al/WSe₂/Al₂O₃ exceeds the phonon radiation limit and increases substantially with T even beyond the Debye temperature. This suggests that inelastic phonon scattering should contribute significantly to the G of WSe₂ interfaces. Our work fills the gap in experimental data on thermal conductance for WX₂ interfaces and offers valuable insights into the underlying thermal transport physics in such systems.

第六族过渡金属二硫族化合物（MoX2和WX2， X=chalcogen）由于其独特的物理性质，在下一代电子器件中引起了相当大的兴趣。尽管在过去的十年中，人们对MoX2界面上的热传递进行了广泛的研究，但对WX2界面的研究仍然有限，而且之前的报道中存在很大的差异，从而模糊了潜在的机制。在这项工作中，我们利用时域热反射（TDTR），通过测量金属/WS2（或WSe2）/Al2O3在80至600 K温度(T)下的界面热导率(G)，实验揭示了声子在WX2界面上传输的控制因素和潜在机制。我们发现，即使是化学气相沉积生长的WS2，在室温下，金属/WS2/Al2O3的G分布在6.4 ~ 13.4 MW m-2 K-1的范围内。通过对皮秒声信号的详细分析和不同条件下制备的样品的比较，我们实验证明，界面键合强度而不是声子密度的不匹配，在WX2界面的G调谐中起决定性作用。此外，我们观察到Al/WSe2/Al2O3的G超过声子辐射极限，即使超过德拜温度，G也随着T的增加而大幅增加。这表明非弹性声子散射对WSe2界面的G有重要贡献。我们的工作填补了WX2界面热导实验数据的空白，并为此类系统的潜在热输运物理提供了有价值的见解。

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引用次数: 0

Generalized rattling and thermal conductivity: Cubic LaRhTe 广义嘎嘎声和热导率：立方LaRhTe

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-12 DOI: 10.1016/j.mtphys.2026.102015

Zhen Wang , Yazhu Xu , Gaofeng Zhao , Zhenzhen Feng , David J. Singh

Thermal conductivity is a key materials parameter that is important in combination with other properties for important applications including electronics, thermal barriers and a variety of energy technologies. There are established trends that are useful in finding materials with desirable thermal conductivity. For example, stable stiff lattices typically yield high thermal conductivity, while materials near instabilities have low thermal conductivity. Rattling is widely applied approach for lowering thermal conductivity and is understood as the incorporation of loosely bound ions in a semiconducting framework. It is manifested in low frequency flat optical phonon branches that cross the acoustic branches. We investigate LaRhTe using global optimization crystal structure determination, anharmonic lattice dynamics, and first principles based characterization of bonding. There are two low energy phases, a hexagonal metallic phase and a cubic semiconducting phase. This cubic phase is predicted to be a low thermal conductivity (1.61 W m⁻¹K⁻¹ at 300 K) semiconductor. We elucidate the origins of its low thermal conductivity finding that strong anharmonic phonon scattering, induced by weak bonding of Rh within the cage-like LaTe network, is important. The Rh atoms contribute to low-frequency phonons, while the La-Te system dominates the high-frequency optical phonon branches. This is unexpected based on the chemical characteristics of Rh chalcogenides and the known thermoelectric behavior of La-Te binary phases. It arises due to the structural constraints in the cubic half-Heusler phase leading to a generalized rattling behavior involving Rh. These results show that the rattling concept is more general than usually assumed and can be operative even without the characteristic rattler induced flat optical branches anticrossing the acoustic branches that are often discussed in the context of low thermal conductivity thermoelectrics.

导热系数是一个关键的材料参数，它与电子、热障和各种能源技术等重要应用的其他性能结合在一起很重要。在寻找具有理想导热性的材料时，有一些既定的趋势是有用的。例如，稳定的刚性晶格通常产生高导热系数，而接近不稳定的材料具有低导热系数。嘎嘎是广泛应用于降低热导率的方法，被理解为在半导体框架中结合松散结合的离子。它表现为低频平面光学声子分支与声学分支交叉。我们使用全局优化晶体结构确定、非调和晶格动力学和基于第一性原理的键合表征来研究LaRhTe。有两种低能相，六方金属相和立方半导体相。该立方相预测为低导热系数（在300 K时为1.61 W m−1K−1）的半导体。我们阐明了其低热导率的起源，发现由笼状LaTe网络中Rh的弱键引起的强非谐波声子散射是重要的。Rh原子对低频声子有贡献，而La-Te系统主导高频光学声子分支。基于Rh硫族化合物的化学特性和已知的La-Te二元相的热电行为，这是出乎意料的。它的产生是由于立方半赫斯勒相的结构约束导致涉及Rh的广义咔嗒行为。这些结果表明，嘎嘎声的概念比通常假设的更普遍，即使没有响尾声诱发的平坦光学分支的特征也可以运作，而声学分支通常在低热导率的热电环境中讨论。

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引用次数: 0

Designing a hybrid α/β-Ga2O3 polymorph heterostructure from strain-relaxed phase transition for high-voltage power diodes 基于应变松弛相变的高压功率二极管α/β-Ga2O3杂化异质结构设计

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-07 DOI: 10.1016/j.mtphys.2026.102010

Kaisen Liu , Songhao Wu , Shulin Hu , Dongyang Han , Li Chen , Gaofeng Deng , Shen Hu , Li Ji , Ping Cui , Jichun Ye , Wenrui Zhang

Ultrawide bandgap (UWBG) gallium oxide (Ga₂O₃) featuring several polymorphs holds great potential for high-power electronics and solar-blind optoelectronics. Designing electronic devices based on hybrid Ga₂O₃ polymorph structures appears highly attractive, but it meets persistent obstacles from epitaxy challenges and dopant activation problems. This study reports a 3 kV-class lateral Schottky barrier diode (SBD) based on a unique heteroepitaxial α/β-Ga₂O₃ heterostructure composed of conductive β-Ga₂O₃ domains embedded in an insulating α-Ga₂O₃ matrix. The α/β-Ga₂O₃ heterostructure is constructed from a strain-relaxed α-to-β Ga₂O₃ phase transition that strongly depends on the substrate orientation and film thickness. The formation of the β-Ga₂O₃ phase presents a minor impact on the crystallinity of the α-Ga₂O₃ matrix and exhibits more readily dopant activation during the sputtering growth. The lateral SBD based on this hybrid α/β-Ga₂O₃ heterostructure combines the benefits of efficient carrier transport in β-Ga₂O₃ and the superior breakdown field in α-Ga₂O₃, thus enabling a decent rectifying behavior and a 3 kV breakdown voltage two times larger than the single-phase β-Ga₂O₃ diode. This study provides critical insights into the phase-design strategy for developing advanced UWBG electronic devices.

超宽带隙（UWBG）氧化镓（Ga2O3）具有多种多晶型，在大功率电子和太阳盲光电子领域具有巨大的潜力。设计基于杂化Ga2O3多晶结构的电子器件具有很高的吸引力，但它遇到了外延挑战和掺杂剂激活问题的持续障碍。本研究报道了一种基于α/β-Ga2O3异质结构的3 kv级横向肖特基势垒二极管（SBD），该异质结构由导电β-Ga2O3畴嵌入绝缘α- ga2o3基体组成。α/β-Ga2O3异质结构是由应变松弛的α -β Ga2O3相变形成的，该相变强烈依赖于衬底取向和薄膜厚度。β-Ga2O3相的形成对α-Ga2O3基体的结晶度影响较小，在溅射生长过程中更容易发生掺杂活化。基于α/β-Ga2O3杂化异质结构的横向SBD结合了β-Ga2O3高效载流子输运和α- ga2o3优越击穿场的优点，从而实现了良好的整流行为和3 kV击穿电压，击穿电压是单相β-Ga2O3二极管的两倍。该研究为开发先进的UWBG电子器件的相位设计策略提供了重要的见解。

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引用次数: 0

Expanding the trilayer Ruddlesden-Popper nickelate family: Synthesis and characterization of Sm4Ni3O10-δ single crystals 扩展三层Ruddlesden-Popper镍酸盐家族：Sm4Ni3O10-δ单晶的合成与表征

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-01 DOI: 10.1016/j.mtphys.2025.102005

Yuhang Zhang, Tian-Yi Li, Xiyu Zhu, Ying-Jie Zhang, Shengtai Fan, Qing Li, Hai-Hu Wen

The discovery of high-temperature superconductivity in Ruddlesden-Popper (RP) nickelates has attracted significant attention. Bulk superconductivity emerges under pressure in trilayer nickelates La₄Ni₃O_10-δ (T_c ≈ 30 K) and Pr₄Ni₃O_10-δ (T_c ≈ 40.5 K), where the reduced ionic radius of Pr³⁺ may generate internal chemical pressure and enhance T_c. However, synthesizing trilayer RP phases with smaller rare-earth elements (Ln) is extremely challenging. So far, only the La, Pr, and Nd analogues have been synthesized with stable phases in the single rare-earth form. Here we report the first successful high-pressure and high-temperature (HPHT) synthesis of samarium-based compound Sm₄Ni₃O_10-δ. Magnetization and transport measurements consistently confirm a density wave (DW) transition at ∼180 K at ambient pressure. Through a careful fitting to the structural data of Sm₄Ni₃O_10-δ, it is found that the bond angle of (Ni−O−Ni) associating with the interlayer apical oxygen is much smaller than 180°, which was assumed to be the key factor for the occurrence of superconductivity. By applying pressures up to 80 GPa, despite partial suppression of insulating behavior and the DW order, but superconductivity is not observed in our present study. Density functional theory calculations suggest that the

3 d_{z^{2}}

and

3 d_{x^{2} - y^{2}}

are separated from other t_2g orbitals and make a primary contribution to the density of states at the Fermi energy. The newly synthesized trilayer nickelate Sm₄Ni₃O_10-δ offers a unique platform for probing the fundamental physics of RP nickelates.

Ruddlesden-Popper （RP）镍酸盐中高温超导性的发现引起了人们的广泛关注。三层镍酸盐La4Ni3O10-δ (Tc≈30 K)和Pr4Ni3O10-δ (Tc≈40.5 K)在压力下呈现大块超导性，其中Pr3+离子半径的减小可能产生内部化学压力，提高Tc。然而，用较小的稀土元素（Ln）合成三层RP相是极具挑战性的。到目前为止，只有La， Pr和Nd类似物以单一稀土形式合成了稳定相。在这里，我们报道了首次成功的高压高温（HPHT）合成钐基化合物Sm4Ni3O10-δ。磁化和输运测量一致地证实了在环境压力下~ 180 K的密度波（DW）跃迁。通过对Sm4Ni3O10-δ结构数据的仔细拟合，发现（Ni−O−Ni）与层间顶端氧缔合的键角远小于180°，这被认为是超导现象发生的关键因素。通过施加高达80gpa的压力，尽管部分抑制了绝缘行为和DW顺序，但在我们的研究中没有观察到超导性。密度泛函理论计算表明，3dz2和3dx2−y2轨道与其他t2g轨道分离，并对费米能量的态密度做出了主要贡献。新合成的三层镍酸盐Sm4Ni3O10-δ为探索RP镍酸盐的基本物理特性提供了一个独特的平台。

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引用次数: 0

Design and analysis of an ultra-thin metamaterial absorber for C, X, Ku and K band applications C， X， Ku和K波段超薄超材料吸收体的设计和分析

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-01 DOI: 10.1016/j.mtphys.2025.102008

Baoqin Lin, Wenzhun Huang, Zuliang Wang, Kaibo Si, Xiaohua Zhou, Fei Xu

Metamaterial absorbers (MMAs) are a class of artificially engineered materials designed to achieve highly efficient electromagnetic (EM) wave absorption, and a large number of MMAs have been proposed in recent years. However, various existing MMAs often suffer from a trade-off between absorption bandwidth and structural thickness, those capable of achieving ultra-wideband absorption with ultra-thin profiles remain very scarce. To address this bottleneck, this study proposes a dual-layer ultra-thin MMA comprising two layers of periodically patterned resistive films integrated into a grounded dual-layer dielectric substrate. Numerical simulations and experimental verifications demonstrate that the MMA can achieve over 90 % absorption across an ultra-wide frequency range covering C, X, Ku, and K bands under normal incidence of arbitrarily polarized waves, but its total thickness is merely 0.075λ_L (where λ_L denotes the wavelength at the lowest absorption frequency), thus yielding an exceptional bandwidth-to-thickness ratio (BTR) of 11.43—surpassing numerous previous designs reported in recent literature. In addition, the MMA can maintain over 95 % absorption for transverse-magnetic (TM) waves even at incident angles up to 60°. The absorption mechanism of the MMA is theoretically elucidated via interference theory, with results basically consistent with simulations and measurements. The combination of ultra-wideband, ultra-thin profile, polarization insensitivity, and wide-angle stability makes the MMA highly promising for applications in radar stealth and electromagnetic interference suppression.

超材料吸波器是一类为实现高效电磁波吸收而设计的人工工程材料，近年来被大量提出。然而，现有的各种mma往往受到吸收带宽和结构厚度之间的权衡的影响，那些能够以超薄轮廓实现超宽带吸收的mma仍然非常稀缺。为了解决这一瓶颈，本研究提出了一种双层超薄MMA，该MMA由两层周期性图案电阻膜集成到接地的双层介电衬底中。数值模拟和实验验证表明，在任意极化波的正常入射下，MMA可以在覆盖C、X、Ku和K波段的超宽频率范围内实现90%以上的吸收，但其总厚度仅为0.075λL （λL表示最低吸收频率的波长），因此产生了11.43的特殊带宽/厚度比（BTR），超过了最近文献中报道的许多先前设计。此外，即使在入射角度高达60°的情况下，MMA对横磁（TM）波也能保持95%以上的吸收率。通过干涉理论对MMA的吸收机理进行了理论解释，结果与模拟和实测结果基本一致。超宽带、超薄外形、偏振不敏感和广角稳定性的结合使MMA在雷达隐身和电磁干扰抑制方面具有很大的应用前景。

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引用次数: 0

Stable memristive switching mechanism in CeO2/a-Ga2O3 heterostructure toward synaptic plasticity and logical operations CeO2/a-Ga2O3异质结构中突触可塑性和逻辑运算的稳定忆阻开关机制

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-01 DOI: 10.1016/j.mtphys.2026.102014

Zhihao Yu, Zhenyang Wang, Fengmin Wu, Chao Wu, Daoyou Guo

Ga₂O₃ has emerged as a highly promising candidate for next-generation memristive materials, owing to its ultra-wide bandgap, exceptional chemical stability, and tunable defect energy states. However, single-layer Ga₂O₃ memristors often suffer from unstable switching voltages caused by the random formation and rupture of conductive filaments, hindering their practical application. In this work, a CeO₂/amorphous-Ga₂O₃ (a-Ga₂O₃) heterostructure memristor with a high oxygen-vacancy gradient was fabricated by employing oxygen-vacancy-rich CeO₂ as an oxygen-vacancy reservoir. The conductance change arises from reversible vacancy migration rather than filament formation in this device, ensuring stable and uniform switching. The device exhibits excellent switching uniformity, with the coefficient of variation for V_set and V_reset as low as 0.18 and 0.15, respectively, which are significantly improved compared with those of the single-layer a-Ga₂O₃ device (0.40 and 0.53, respectively). Moreover, both the HRS and LRS states remain highly stable for up to 10⁴ s under dark conditions. This work provides an effective approach to achieve stable, uniform, and non-filamentary resistive switching in wide-bandgap oxide memristors, paving the way for reliable neuromorphic and logic device applications.

由于其超宽的带隙、优异的化学稳定性和可调的缺陷能态，Ga2O3已成为下一代记忆材料的极有前途的候选者。然而，单层Ga2O3忆阻器由于导电丝的随机形成和断裂，导致开关电压不稳定，阻碍了其实际应用。本文以富氧空位的CeO2为氧空位储层，制备了具有高氧空位梯度的CeO2/非晶ga2o3异质结构忆阻器。在该器件中，电导变化是由可逆空位迁移而不是灯丝形成引起的，从而保证了开关的稳定和均匀。该器件具有优异的开关均匀性，Vset和Vreset的变化系数分别低至0.18和0.15，与单层a-Ga2O3器件（分别为0.40和0.53）相比有显著提高。此外，在黑暗条件下，HRS和LRS状态在长达104 s的时间内保持高度稳定。这项工作为实现宽带隙氧化物忆阻器的稳定、均匀和非丝状电阻开关提供了一种有效的方法，为可靠的神经形态和逻辑器件应用铺平了道路。

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引用次数: 0

Defect engineering enables ultra-stable radiation-resistant optical transparency in polycrystalline Gd2Zr2O7 ceramics 缺陷工程使多晶Gd2Zr2O7陶瓷具有超稳定的抗辐射光学透明度

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-01 DOI: 10.1016/j.mtphys.2025.102009

Lexing Liang , Cong Zhang , Mao Deng , Junjing Duan , Xiaolan Zhou , Zaixin Wei , Kailei Lu , Yanli Shi , Zhangyi Huang , Jianqi Qi , Tiecheng Lu

Highly transparent polycrystalline gadolinium zirconate (Gd₂Zr₂O₇, GZO) ceramics are excellent candidates for mixed gamma (γ) and neutron radiation shielding, but suffer from γ-induced color centers. To address this, we introduce a Ce-doping–mediated defect-engineering strategy, demonstrating that the Ce valence state is the critical switch. We show that Ce⁴⁺-rich (air-annealed) samples exhibit exceptional radiation-hardening, whereas Ce³⁺-rich (vacuum-sintered) samples show catastrophic sensitization. It is confirmed that Ce⁴⁺ acts as a preferential electron trap, competitively suppressing color center formation. As a result, the optimized Ce⁴⁺-rich samples exhibit a γ-induced transmittance loss of less than 4 % (at 100 kGy) and maintain excellent transparency (71.8 % at 450 nm), vastly outperforming commercial ZF6 lead glass (which suffers a 52.6 % loss). Furthermore, GZO:Ce demonstrates 20 % higher γ attenuation (0.373 cm⁻¹ for ⁶⁰Co) and exceptional thermal neutron shielding (cross-section of 688.22 cm⁻¹), combined with excellent mechanical hardness (∼11.5 GPa) and superior corrosion resistance in both acidic and alkaline media. This work establishes Ce-doped GZO as a scalable and durable ceramic platform for γ/n shielding windows, and highlights valence-state and defect engineering as a powerful strategy for the rational design of radiation-tolerant transparent materials.

高透明多晶锆酸钆（Gd2Zr2O7， GZO）陶瓷是混合γ (γ)和中子辐射屏蔽的优秀候选人，但受到γ诱导色心的影响。为了解决这个问题，我们引入了Ce掺杂介导的缺陷工程策略，证明Ce价态是关键开关。我们发现富Ce4+（空气退火）样品表现出异常的辐射硬化，而富Ce3+（真空烧结）样品表现出灾难性的敏化。证实了Ce4+作为优先电子陷阱，竞争性地抑制了色心的形成。结果，优化后的富Ce4+样品显示出γ诱导的透射率损失小于4%（在100 kGy时），并保持良好的透明度（在450 nm时为71.8%），大大优于商用ZF6铅玻璃（其损失为52.6%）。此外，GZO:Ce在酸性和碱性介质中表现出高20%的γ衰减（60Co为0.373 cm−1）和出色的热中子屏蔽（横截面为688.22 cm−1），结合优异的机械硬度（~ 11.5 GPa）和优异的耐腐蚀性。这项工作建立了ce掺杂GZO作为γ/n屏蔽窗口的可扩展和耐用陶瓷平台，并强调了价态和缺陷工程作为合理设计耐辐射透明材料的有力策略。

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引用次数: 0

Magnetic, transport, and Raman properties of the layered charge density wave antiferromagnet EuTe4 under ambient and high pressures 层状电荷密度波反铁磁体EuTe4在环境和高压下的磁性、输运和拉曼特性

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-01-01 DOI: 10.1016/j.mtphys.2026.102011

Jin Jiang , Shuyang Wang , Chao An , Zhitao Zhang , Langsheng Ling , Yuqiang Liu , Xiaoping Yang , Yonghui Zhou , Xuliang Chen , Zhaorong Yang

We present a comprehensive study of EuTe₄ single crystals using axis-resolved magnetization, electrical transport, electron spin resonance, and Raman spectroscopy at ambient pressure, complemented by high-pressure measurements up to 47.3 GPa. At ambient pressure, EuTe₄ is determined as an A-type antiferromagnet (T_N∼7.1 K) with localized Eu²⁺ spins pointing along the a axis and aligning ferromagnetically within the basal plane and antiferromagnetically along the c axis. A spin-flop transition occurs below T_N at approximately 3/8 of the saturation magnetization when the magnetic field is applied along the a axis, the easy magnetization direction. Pronounced negative magnetoresistance accompanies this field-driven spin reorientation, reminiscent of the giant magnetoresistance effect in artificial magnetic superlattices. The pressure–temperature phase diagram reveals a semiconductor-to-metal transition with the suppression of CDW-related resistivity hysteresis near 4 GPa, a change in the T_N evolution at ∼11 GPa, and an antiferromagnetic-to-nonmagnetic transition near 22 GPa, likely associated with pressure-induced lattice modulations. These results provide crucial insight into the interplay among charge, spin, and lattice degrees of freedom in layered EuTe₄.

我们在环境压力下利用轴分辨磁化、电输运、电子自旋共振和拉曼光谱对EuTe4单晶进行了全面的研究，并通过高达47.3 GPa的高压测量进行了补充。在环境压力下，EuTe4被确定为a型反铁磁体（TN ~ 7.1 K），其局域化Eu2+自旋指向a轴，在基面上呈铁磁排列，并沿c轴呈反铁磁排列。当磁场沿易磁化方向A轴施加时，在饱和磁化强度约为3/8时，在TN以下发生自旋触发器跃迁。明显的负磁阻伴随着磁场驱动的自旋重定向，让人联想到人工磁超晶格中的巨磁阻效应。压力-温度相图揭示了半导体到金属的转变，cdw相关的电阻率滞后在4 GPa附近受到抑制，TN在~ 11 GPa时发生变化，在22 GPa附近发生反铁磁性到非磁性的转变，可能与压力诱导的晶格调制有关。这些结果为层状EuTe4中电荷、自旋和晶格自由度之间的相互作用提供了重要的见解。

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引用次数: 0