Chinese Journal of Physics最新文献_第2页

Migration of a slip-spin solid spherical particle in a micropolar fluid-filled circular cylindrical tube 滑旋固体球形粒子在充满微极性流体的圆柱形圆管中的迁移

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-25 DOI: 10.1016/j.cjph.2024.10.024

Ahmed G. Salem

A combined study analytically and numerically for the axially symmetric creeping flow due to a slip-spin solid sphere surface moving in a microstructure fluid of micropolar type along the centreline of a circular cylindrical tube is introduced. This investigation was presented under low Reynolds number conditions. A general solution is obtained by superposing the essential solutions in both spherical and cylindrical coordinates to solve the Eringen micropolar field equations. The condition of the microrotation, along with couple stress, is used at the surface of the solid particle; while the microrotation is used at the inner cylindrical surface. Boundary conditions are imposed initially on the inner cylindrical surface using Fourier transforms and subsequently on the outer surface of the solid particle using a collocation technique. This paper aims to study the wall interaction problem of a translating slip-spin solid spherical particle in a micropolar fluid along the centreline of a circular cylindrical tube. The study also investigates the effect of the addition of slip conditions for velocity and microrotation on the surface of a solid particle. There is good convergence in the numerical findings obtained for the normalised hydrodynamic drag force (the tube-corrected factor) applying on the surface of the solid particle for several values of the micropolarity coefficient, slip-spin coefficients, and the ratio between the radius of the solid particle and tube. Regarding the flow of a solid spherical particle along the centreline of a cylindrical tube, our drag findings compare favourably to the solutions found in the literature. We found that the normalised drag force acting on the solid particle monotonically increases with the increase of the particle-to-tube radius ratio and reaches infinity in the limitless, with the increase of the micropolarity coefficient, and with the increase of the slip-spin coefficients for a steady ratio of particle-to-tube radius.

本文介绍了对滑旋固体球面在沿圆柱管中心线运动的微波型微结构流体中产生的轴对称蠕动流进行的分析和数值综合研究。该研究是在低雷诺数条件下进行的。通过叠加球坐标和圆柱坐标下的基本解来求解艾林根微极场方程，从而获得了一般解。在固体颗粒表面使用了微旋转条件和耦合应力；而在内圆柱表面使用了微旋转条件。边界条件最初通过傅立叶变换施加在内圆柱面上，随后通过搭配技术施加在固体颗粒的外表面上。本文旨在研究滑旋固体球形粒子在微极性流体中沿圆柱管中心线平移时的壁面相互作用问题。研究还探讨了在固体颗粒表面添加速度和微旋转滑移条件的影响。对于固体颗粒表面上的归一化流体动力阻力（管校正系数），在微极性系数、滑旋系数和固体颗粒与管半径之比取值时，数值结果收敛性良好。关于固体球形粒子沿圆柱形管中心线的流动，我们的阻力研究结果与文献中的解决方案相比毫不逊色。我们发现，作用在固体颗粒上的归一化阻力随着颗粒与管子半径比的增大而单调增大，并在无限大的情况下达到无穷大；在颗粒与管子半径比稳定的情况下，随着微极性系数的增大以及滑旋系数的增大而增大。

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引用次数: 0

Impact of temperature-dependent viscosity on linear and weakly nonlinear stability of double-diffusive convection in viscoelastic fluid 温度相关粘度对粘弹性流体中双扩散对流的线性和弱非线性稳定性的影响

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-24 DOI: 10.1016/j.cjph.2024.10.011

Joginder Singh Dhiman , Khushboo Gupta , Praveen Kumar Sharma

The impact of temperature-dependent viscosity on the double-diffusive viscoelastic convective fluids is investigated, with applications in heat transfer, polymer processing, food industry, biomedical engineering, etc. Both linear and weakly nonlinear analyses are carried out to determine the stability of fluids using the Oldroyd-B model. Analytical criteria for the onset of linear stationary and oscillatory convection are derived. The effects of rheological parameters, linearly and exponentially varying viscosity, salinity Rayleigh number and Prandtl number on the system’s stability are investigated. Linear stability analysis reveals that the interaction between thermal and solute diffusions with rheological parameters favours oscillatory convection over stationary convection. In weakly nonlinear theory, a power series expansion derives a Landau amplitude equation, allowing heat and mass transfer analysis in viscoelastic fluids with temperature-dependent viscosity. Numerical results highlight the effects of variable viscosity on heat and mass transfer rates, represented by Nusselt and Sherwood numbers. Further, the weakly non-linear stability analysis evaluates the impact of the Prandtl number, rheological parameters and salinity Rayleigh number on heat and mass transfer rates. These findings are compared with existing results to validate and enhance our understanding of fluid behaviour under different conditions.

研究了温度相关粘度对双扩散粘弹性对流流体的影响，并将其应用于传热、聚合物加工、食品工业、生物医学工程等领域。利用 Oldroyd-B 模型进行了线性和弱非线性分析，以确定流体的稳定性。得出了线性静止和振荡对流开始的分析标准。研究了流变参数、线性和指数变化的粘度、盐度雷利数和普朗特尔数对系统稳定性的影响。线性稳定性分析表明，热扩散和溶质扩散与流变参数之间的相互作用有利于振荡对流，而不是静止对流。在弱非线性理论中，通过幂级数展开得出了朗道振幅方程，从而可以分析粘弹性流体中与温度相关的粘度的传热和传质情况。数值结果凸显了粘度变化对传热和传质速率的影响，并以努塞尔特数和舍伍德数表示。此外，弱非线性稳定性分析评估了普朗特数、流变参数和盐度雷利数对传热和传质速率的影响。这些研究结果与现有结果进行了比较，以验证并加深我们对不同条件下流体行为的理解。

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引用次数: 0

Three-phase lag model for thermal conductivity of a thermo-viscoelastic porous medium 热弹性多孔介质导热性的三相滞后模型

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-22 DOI: 10.1016/j.cjph.2024.10.025

Montaser Fekry , Mohamed I.A. Othman

This paper investigates the propagation of waves and the thermal behavior in a thermo-viscoelastic porous medium using the three-phase-lag (TPL) model which accounts for phase lags in the heat flux vector, temperature gradient and thermal displacement gradient. The study aims to capture the interactions between thermal, mechanical, and structural properties of the thermo-viscoelastic porous, isotropic, homogeneous medium. The governing equations, incorporating the TPL heat conduction law and constitutive relations for the viscoelastic porous material, are derived and analyzed. The impact of relaxation times, porosity, and viscoelastic parameters on heat propagation is investigated through analytical solutions by normal modal analysis. Analytical representations of various physical quantities (stresses components, displacements, temperature,…) in the material's domain are derived. These expressions are then assessed numerically for a specific material, with the outcomes depicted graphically. A comparison is made between the predictions of the three-phase-lag (TPL), the dual-phase-lag (DPL) and Lord–Shulman (L–S) theories in the absence and presence of voids.

本文使用三相滞后（TPL）模型研究了热粘弹性多孔介质中波的传播和热行为，该模型考虑了热通量矢量、温度梯度和热位移梯度的相位滞后。该研究旨在捕捉热-粘弹性多孔、各向同性、均质介质的热、机械和结构特性之间的相互作用。推导并分析了包含 TPL 热传导定律和粘弹性多孔材料构成关系的控制方程。通过法向模态分析的分析解，研究了弛豫时间、孔隙率和粘弹性参数对热传播的影响。推导出了材料域中各种物理量（应力分量、位移、温度......）的分析表达式。然后，针对特定材料对这些表达式进行数值评估，并用图形对结果进行描述。比较了三相滞后理论（TPL）、双相滞后理论（DPL）和 Lord-Shulman 理论（L-S）在无空隙和有空隙情况下的预测结果。

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引用次数: 0

Accurate measurement of wavelength-Dependent beam parameters of a supercontinuum light source focused by a lensed fiber probe 精确测量透镜光纤探头聚焦的超连续光源的波长相关光束参数

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-20 DOI: 10.1016/j.cjph.2024.10.023

Kuan-Yuan Chang , Jun-Cheng Hsu , Jia-Ming Liu

In this work, an supercontinuum (SC) light is focused by an optical lensed fiber (OLF). We demonstrate a new method to meticulously analyze multi-wavelength beam parameters of the OLF probe and the focused SC beam by applying a spectrometer to measure the variation of back-coupling efficiency for different wavelengths. By contrast, inevitable and relatively small errors in the OLF parameters that are obtained by using the conventional method lead to significant errors in the spatial information of the focused SC beam. Therefore, this method is expected to be a necessary calibration procedure for a system with an OLF probe. The SC beam focused by our OLF has little chromatic aberration in the beam size and the focal length in a range of approximately 120 μm.

在这项工作中，超连续（SC）光被光学透镜光纤（OLF）聚焦。我们展示了一种新方法，通过使用光谱仪测量不同波长背耦合效率的变化，细致分析 OLF 探针和聚焦 SC 光束的多波长光束参数。相比之下，使用传统方法获得的 OLF 参数不可避免地会出现相对较小的误差，从而导致聚焦 SC 光束的空间信息出现重大误差。因此，这种方法有望成为带有 OLF 探头的系统的必要校准程序。我们的 OLF 聚焦的 SC 光束在大约 120 μm 的光束尺寸和焦距范围内几乎没有色差。

引用次数: 0

Exploring Tsallis thermodynamics for boundary conformal field theories in gauge/gravity duality 探索轨距/引力对偶性边界共形场论的查里斯热力学

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-19 DOI: 10.1016/j.cjph.2024.10.015

Y. Sekhmani , G.G. Luciano , S.K. Maurya , J. Rayimbaev , B. Pourhassan , M.K. Jasim , A. Rincon

Inspired by AdS/CFT interpretation Karch and Robinson (2015), we analyze thermodynamics for thermal boundary conformal field theories (CFT) that are dual to four-dimensional charged anti-de Sitter (AdS) black holes embedded in 11-dimensional M-theory-inspired models with

A d S_{4} \times S^{7}

space–time, employing the framework of Tsallis entropy. The latter is recognized as a nonadditive extension of the Boltzmann–Gibbs entropy that can satisfy the thermodynamic extensivity for black holes. Specifically, we consider AdS black holes in

A d S_{4} \times S^{7}

spacetime, interpreting the number of M2-branes as a thermodynamic variable. Using the Tsallis entropy enables us to highlight peculiar thermodynamic features, resorting to essential tools such as the chemical potential and Gibbs energy while examining phase transitions along iso-charge partitions. Then, we leveraged a class of geometrothermodynamic formalisms, including Weinhold, Ruppeiner, Quevedo I, and II metrics. Quevedo’s formulations provide richer information about phase transitions than the first two methods. Our study sheds new light on AdS black holes in a thermodynamically proper context, deepening our understanding of the role of non-extensivity in the critical behavior of such complex systems.

受AdS/CFT诠释Karch和Robinson（2015）的启发，我们采用Tsallis熵框架，分析了嵌入AdS4×S7时空的11维M理论启发模型中与四维带电反德西特（AdS）黑洞对偶的热边界共形场论（CFT）的热力学。后者被认为是波兹曼-吉布斯熵的非加性扩展，可以满足黑洞的热力学扩展性。具体来说，我们考虑了 AdS4×S7 时空中的 AdS 黑洞，将 M2ranes 的数量解释为一个热力学变量。利用查里斯熵，我们可以突出奇特的热力学特征，借助化学势和吉布斯能等基本工具，同时研究等电荷分区的相变。然后，我们利用了一类几何热力学形式，包括 Weinhold、Ruppeiner、Quevedo I 和 II 度量。与前两种方法相比，Quevedo 公式提供了更丰富的相变信息。我们的研究从热力学的角度为 AdS 黑洞提供了新的视角，加深了我们对非扩展性在这类复杂系统临界行为中的作用的理解。

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引用次数: 0

Congested traffic patterns of mixed lattice hydrodynamic model combining the perceptual range differences with passing effect 将感知范围差异与通过效应相结合的混合网格流体力学模型的拥堵交通模式

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-18 DOI: 10.1016/j.cjph.2024.10.022

Cong Zhai , Weitiao Wu , Jiyong Zhang , Yingping Xiao

With the aid of Vehicle-to-everything (V2X) technologies for network connectivity, connected autonomous vehicles (CAVs) can broaden the drivers' perceptual boundaries and receive a greater quantity of exogenous vehicle information, thereby governing the vehicle's acceleration information of the next moment. Nonetheless, constrained by contemporary communication networks and sophisticated vehicle control technology, the process of promoting CAVs is long-lasting, and throughout this stage of transition, both CAVs and human-driven vehicles (HDVs) will coexist on the road. Moreover, passing behaviour has received limited attention in the research on the traffic flow models despite being a fundamental microscopic driving behaviour. To bridge these gaps, we introduce the percentage ratios of CAVs into the lattice hydrodynamic model by integrating the perceptual range differences between two different types of vehicles with passing effects. Subsequently, the stability norm associated with the new model is ascertained by performing the linear stability analysis. When the stability condition is not achieved, we investigate the complex behaviour of the new model. The associated existing conditions and the modified Korteweg-de Vries (mKdV) equation are determined simultaneously. When the passing ratio is inadequate, no jam and kink jam make up the whole phase region; when the passing ratio surpasses the minimum, the initial unstable region can be segregated into two extra segments: the chaotic sub-region and the kink jam sub-region, and the density wave progressively transitions from being a kink-Bando traffic wave to a chaotic phase. The findings of the numerical experiment are consistent with with the theoretical derivation.

借助车对物（V2X）网络连接技术，互联自动驾驶汽车（CAV）可以拓宽驾驶员的感知边界，接收更多的外源车辆信息，从而控制车辆下一刻的加速信息。然而，受制于当代通信网络和复杂的车辆控制技术，CAV 的推广过程是漫长的，在这一过渡阶段，CAV 和人类驾驶的车辆（HDV）将在道路上并存。此外，尽管超车行为是一种基本的微观驾驶行为，但在交通流模型研究中受到的关注有限。为了弥补这些不足，我们将两种不同类型车辆之间的感知范围差异与超车效应整合在一起，从而将 CAV 的百分比率引入晶格流体力学模型。随后，通过线性稳定性分析确定与新模型相关的稳定性规范。当未达到稳定条件时，我们将研究新模型的复杂行为。同时确定相关的现有条件和修正的 Korteweg-de Vries（mKdV）方程。当通过比不足时，无堵塞和扭结堵塞构成了整个相区；当通过比超过最小值时，初始不稳定区域可分离为两个额外的部分：混乱子区域和扭结堵塞子区域，密度波从扭结-班多交通流波逐渐过渡到混乱相。数值实验结果与理论推导一致。

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引用次数: 0

Nonlinear tunneling of partially nonlocal dark-dark annular sneaker waves under a parabolic potential 抛物线势下部分非局部暗-暗环形运动鞋波的非线性隧道效应

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-18 DOI: 10.1016/j.cjph.2024.10.012

Yu Zhu, Jing Yang, Zezhou Chen, Wei Qin, Jitao Li

Annular rogue waves have been reported, but little is known about how to excite and control them, particularly their tunneling effect. From the projecting relation between the vector partially nonlocal nonlinear Schrödinger equation possessing different transverse-directional diffractions and the parabolic potential and vector constant-coefficient nonlinear Schrödinger equation, via the Darboux method, partially nonlocal dark-dark annular sneaker wave approximate solutions are found. Two aspects of the study are carried out: (i) four excitations of partially nonlocal dark-dark annular sneaker waves including complete, delayed, valley-maintained and prohibitive excitations and (ii) nonlinear tunneling of partially nonlocal dark-dark annular sneaker waves are studied. The influence of two parameters

R

and

l

on dark-dark annular sneaker waves is also analyzed. The partially nonlocal characteristics of dark-dark annular sneaker waves passing through the nonlinear well implies that the layer of annular sneaker wave structures increases in

x y z

-coordinate when the value of the Hermite parameter adds. These findings will further our understanding of the partially nonlocal nonlinear wave in the disciplines of cold atom and optical communication.

环状流氓波已有报道，但对如何激发和控制它们，尤其是它们的隧道效应，却知之甚少。从具有不同横向衍射的矢量部分非局域非线性薛定谔方程与抛物势和矢量恒系数非线性薛定谔方程之间的投影关系出发，通过达尔布方法，找到了部分非局域暗-暗环形流氓波近似解。研究包括两个方面：(i) 部分非局部暗-暗环形运动波的四种激波，包括完全激波、延迟激波、谷保持激波和禁止激波；以及 (ii) 部分非局部暗-暗环形运动波的非线性隧穿。还分析了两个参数 R 和 l 对暗暗环形运动波的影响。通过非线性井的暗-暗环形运动波的部分非局部特性意味着，当赫米特参数值增加时，环形运动波结构层在 xyz 坐标上会增加。这些发现将进一步加深我们对冷原子和光通信学科中部分非局部非线性波的理解。

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引用次数: 0

Tip-induced local Fermi level alignment: A Stark shift in vacuum level in scanning tunneling microscope configurations 尖端诱导的局部费米级对准：扫描隧道显微镜配置中真空层的斯塔克偏移

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-16 DOI: 10.1016/j.cjph.2024.10.020

Wei-Bin Su , Wen-Yuan Chan , Shin-Ming Lu , Ho-Hsiang Chang , Chia-Seng Chang

Electric fields in the junction of a scanning tunneling microscope (STM) are generally considered to have a negligible impact on the vacuum level (VL) of materials. We employed field emission resonance (FER) in the STM, combined with the triangular potential model, to measure the VL of the Ag(100) surface under varying electric currents. Unexpectedly, our results reveal that the VL exhibits a linear positive energy shift with increasing electric field strength. We suggest that this Stark shift in the VL arises from local Fermi level alignment induced by the STM tip. Additionally, we examined the VL of Ag islands grown on Cu(111) and Au(111) surfaces under different currents. Despite the Ag island having a lower work function than the Cu(111) and Au(111) surfaces, the energy shift in the VL with respect to the electric field on the Ag island is almost identical to that on the substrate under the same tip structure. This suggests that the Stark shift of the VL is insensitive to the work function. These findings are crucial for utilizing FER to measure local work function variations on surfaces, as the measured value is not influenced by the STM tip structure or the tunneling current, both of which can alter the electric field.

扫描隧道显微镜（STM）结点中的电场通常被认为对材料的真空度（VL）影响微乎其微。我们利用 STM 中的场发射共振（FER），结合三角电位模型，测量了 Ag(100) 表面在不同电流下的真空度。出乎意料的是，我们的结果表明，随着电场强度的增加，VL 呈现线性正能量移动。我们认为，VL 的这种斯塔克偏移是由 STM 针尖诱导的局部费米级对齐引起的。此外，我们还研究了生长在铜（111）和金（111）表面的银岛在不同电流下的 VL。尽管银岛的功函数低于铜（111）和金（111）表面，但在相同的针尖结构下，银岛上 VL 相对于电场的能量移动几乎与基底上的相同。这表明 VL 的斯塔克偏移对功函数不敏感。这些发现对于利用 FER 测量表面局部功函数变化至关重要，因为测量值不受 STM 尖端结构或隧道电流的影响，而这两者都会改变电场。

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引用次数: 0

Effect of thin film thickness of ferrofluid on inclined bioconvective flow 铁流体薄膜厚度对倾斜生物对流的影响

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-16 DOI: 10.1016/j.cjph.2024.10.019

Anupam Bhandari

This research examines the effect of variable thin film thickness on the bioconvective ferrofluid flow through a rotating sloped surface when a magnetic field (dipole) is present. Similarity transformation is used to standardize the current model's governing equations. By using a finite element method, the normalized nonlinear differential equations are numerically solved. Variable thickness of ferrofluid thin film and bioconvective parameters (bioconvective Lewis number, bioconvective Peclet number, and micro-organism concentration difference) yield the following results: velocity profiles (radial, tangential, and axial), gravity flow (drainage velocity and induced velocity), temperature profile, concentration profile and microorganism profile. In addition, this investigation examines the density of moving microorganisms as well as local heat and mass transport. The temperature, concentration, radial, axial, drainage, induced, and motile microbe velocity are all improved with increasing film thickness. Variable thickness increases local heat transfer whereas increasing Brownian motion and thermophoresis parameters decreases it. This study could be helpful for self-sterilizing applications and biomedical engineering.

本研究探讨了在存在磁场（偶极子）的情况下，可变薄膜厚度对流经旋转斜面的生物对流铁流体的影响。相似变换用于标准化当前模型的控制方程。通过使用有限元方法，对归一化非线性微分方程进行数值求解。铁流体薄膜厚度和生物对流参数（生物对流路易斯数、生物对流佩克莱特数和微生物浓度差）的变化产生了以下结果：速度剖面（径向、切向和轴向）、重力流（排水速度和诱导速度）、温度剖面、浓度剖面和微生物剖面。此外，这项研究还考察了移动微生物的密度以及局部热量和质量的传输。随着薄膜厚度的增加，温度、浓度、径向、轴向、排水、诱导和移动微生物速度都有所改善。厚度的变化会增加局部传热，而布朗运动和热泳参数的增加则会降低局部传热。这项研究有助于自消毒应用和生物医学工程。

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引用次数: 0

Low-pressure superconductivity of Th-B-H ternary compounds: An insightful study of stable and metastable phases Th-B-H 三元化合物的低压超导性：对稳定相和蜕变相的深入研究

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-16 DOI: 10.1016/j.cjph.2024.10.021

Tian-Tian Liu, Xin Li, Guo-Yong Shi, Juan Hua, Yue-Hua Su, Chao Zhang, Hong Jiang

The low-enthalpy structures of Th-B-H ternary compounds below 50 GPa are investigated by using an efficient framework that combines high-throughput screening, genetic algorithms, and first-principles calculations. Four thermodynamically stable hydrides (Th₂BH₁₁, Th₂BH₁₀, ThB₂H₁₀, and ThBH) and seven thermodynamically metastable hydrides (ThBH₂, ThBH₃, ThBH₄, ThBH₅, ThBH₇, ThB₂H₄, and ThB₃H₃) are revealed. There are no stable thorium boron hydrides at ambient pressure. R3m-ThB₂H₁₀ and R3m-Th₂BH₁₁ are indirect bandgap semiconductors, while R3m-Th₂BH₁₀ and P6/mmm-ThBH show metallic nature. The relatively low λ values of R3m-Th₂BH₁₀ and P6/mmm-ThBH result in their T_c around 5.8 K and 0.1 K at 20 GPa, respectively. Two metastable phases,

F \bar{4} 3 m

-ThBH₅ and P6₃/mmc-ThBH₇, exhibit excellent superconducting properties at low pressures. The values of T_c of

F \bar{4} 3 m

-ThBH₅ and P6₃/mmc-ThBH₇ reach 46.9 K at 20 GPa and 40.0 K at 50 GPa, respectively. Our findings offer valuable insights for discovering and designing superconducting rare earth hydrides under low and even ambient pressures.

通过结合高通量筛选、遗传算法和第一原理计算的高效框架，研究了低于 50 GPa 的 Th-B-H 三元化合物的低焓结构。揭示了四种热力学上稳定的氢化物（Th2BH11、Th2BH10、ThB2H10 和 ThBH）和七种热力学上易变的氢化物（ThBH2、ThBH3、ThBH4、ThBH5、ThBH7、ThB2H4 和 ThB3H3）。在常压下没有稳定的钍硼氢化物。R3m-ThB2H10 和 R3m-Th2BH11 是间接带隙半导体，而 R3m-Th2BH10 和 P6/mmm-ThBH 则显示出金属性质。R3m-Th2BH10 和 P6/mmm-ThBH 的 λ 值相对较低，因此它们在 20 GPa 时的 Tc 分别约为 5.8 K 和 0.1 K。F4¯3m-ThBH5和P63/mmc-ThBH7这两种蜕变相在低压条件下表现出优异的超导特性。F4¯3m-ThBH5 和 P63/mmc-ThBH7 的 Tc 值分别在 20 GPa 和 50 GPa 时达到 46.9 K 和 40.0 K。我们的发现为在低压甚至环境压力下发现和设计超导稀土氢化物提供了宝贵的见解。

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引用次数: 0