Physica E-low-dimensional Systems & Nanostructures最新文献_第7页

Impact of magnetic field on photocurrent: A classical electrodynamic study, simulation, and experimental validation 磁场对光电流的影响：一个经典的电动力学研究、模拟和实验验证

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-19 DOI: 10.1016/j.physe.2025.116390

Mohammed Khalis , Abdennabi Morchid , Rachid Masrour

In this work, we conducted a study aimed at analyzing the impact of uniform electric and magnetic fields on the behavior of charge carriers in a solar cell, with particular focus on the evolution of the photocurrent. Relying on the classical laws of electrodynamics, formulated within a covariant framework, we established the fundamental relationship between the electric field

\vec{E}

and the magnetic field

\vec{B}

through the Lorentz force, without initially accounting for collisional interactions. The equations of motion of electrons and holes—describing in particular the cycloidal trajectories of carriers and the drift velocity resulting from the combined action of the two fields—constitute the theoretical basis of our analysis. The application of this formalism to the operation of a solar cell subjected to a perpendicular magnetic field reveals distinct behaviors depending on the region considered. In the depletion region, where the internal electric field is strong, the influence of the magnetic field is significant and markedly alters carrier trajectories. In contrast, in the neutral regions dominated by diffusive transport, its effect remains negligible. The results confirm that increasing the magnetic field intensity leads to a substantial reduction in the photocurrent. For instance, in a silicon solar cell with a surface area of 100 cm² under

1000 W . m^{- 2}

illumination at 25 °C, MATLAB simulations indicate a decrease in photocurrent from 3.6 A to 2.6 A as the magnetic field increases from 0 to 50 mT. Experimentally, the study of a photovoltaic module with a surface area of 270 cm² under

600 W . m^{- 2}

illumination shows a reduction in photocurrent from 205 to 90 mA, accompanied by an increase in series resistance from 7.76 to 17.70 Ω, under the same magnetic field variation. When the effect of collisional forces is subsequently incorporated into the modeling, the influence of the magnetic field on both series resistance and photocurrent reduction becomes even more pronounced. These findings highlight an excellent agreement between the modeling—which simultaneously accounts for electrical, magnetic, and collisional contributions—and the experimental observations, thereby validating the relevance of the proposed model and its ability to faithfully describe the behavior of solar cells in the presence of a magnetic field.

在这项工作中，我们进行了一项研究，旨在分析均匀电场和磁场对太阳能电池中载流子行为的影响，特别关注光电流的演变。依靠在协变框架内表述的经典电动力学定律，我们通过洛伦兹力建立了电场E→和磁场B→之间的基本关系，而没有最初考虑碰撞相互作用。电子和空穴的运动方程——特别是描述载流子的摆线轨迹和两个场共同作用所产生的漂移速度——构成了我们分析的理论基础。将这种形式应用于受垂直磁场影响的太阳能电池的操作，揭示了不同区域所考虑的不同行为。在耗尽区，内部电场强，磁场的影响是显著的，显著改变载流子轨迹。相反，在以扩散输运为主的中性区，其影响仍然可以忽略不计。结果证实，增加磁场强度会导致光电流的大幅降低。例如,在硅太阳能电池表面面积100 cm2低于1000 w.m−2照明25°C, MATLAB仿真表明减少光电流从3.6到2.6随着磁场的增加从0到50吨。实验,研究光伏模块的表面面积270 cm2低于600 w.m−2照明显示了从205年到90年减少光电流,伴随着串联电阻的增加从7.76到17.70Ω,在相同的磁场变化下。当碰撞力的影响随后被纳入建模时，磁场对串联电阻和光电流减小的影响变得更加明显。这些发现突出了模型（同时考虑了电、磁和碰撞的影响）与实验观察之间的良好一致性，从而验证了所提出模型的相关性及其在磁场存在下忠实地描述太阳能电池行为的能力。

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引用次数: 0

Analytical modeling of electron mobility in non-degenerate and degenerate bulk n-Ge1-xSnx 非简并体和简并体n-Ge1-xSnx中电子迁移率的分析建模

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-15 DOI: 10.1016/j.physe.2025.116388

Bratati Mukhopadhyay, P.K. Basu

Direct bandgap Ge_1-xSn_x (x > 0.08) alloys have emerged as highly promising materials for next-generation high-speed electronic, thermoelectric, and photonic devices, owing to their tunable band structure and compatibility with standard CMOS technology on silicon platforms. The transition from indirect to direct band gap for Sn concentration exceeding 8 % has made these alloys attractive for photonic applications such as mid-infrared lasers, modulators, and photodetectors, particularly in the 2–5 μm wavelength range. An earlier study predicted that the electron mobility in the non-degenerate Ge_1-xSn_x alloy would increase by 50 times for x ≥ 0.08 from the value in pure Ge (3900 cm²/V-sec) due to increased separation between Γ and L valleys and consequent reduction in intervalley scattering. In the present work, a realistic theoretical estimate is made of mobility of bulk Ge_1-xSn_x under both non-degenerate and degenerate condition for a wide range of Sn concentration (0 < x < 0.2) covering indirect and direct bandgap nature of the alloy. The theoretical values of mobility show excellent agreement with the experimental values reported for x = 0.02, and satisfactory agreement for x = 0.125. For the calculation of mobility, scattering by phonons (deformation potential acoustic, optical and intervalley), alloy-disorder, impurity as well as electron-electron scattering have been taken into consideration.

直接带隙Ge1-xSnx （x > 0.08）合金由于其可调谐的能带结构和与硅平台上的标准CMOS技术的兼容性，已成为下一代高速电子、热电和光子器件的极具前景的材料。当锡浓度超过8%时，从间接带隙到直接带隙的转变使得这些合金在中红外激光器、调制器和光电探测器等光子应用中具有吸引力，特别是在2-5 μm波长范围内。先前的一项研究预测，当x≥0.08时，非简并Ge1-xSnx合金中的电子迁移率将比纯Ge （3900 cm2/V-sec）增加50倍，这是由于Γ和L山谷之间的分离增加，从而减少了山谷间散射。在本工作中，对非简并和简并条件下的大块Ge1-xSnx的迁移率进行了现实的理论估计，该迁移率适用于广泛的Sn浓度范围（0 < x < 0.2），涵盖了合金的间接和直接带隙性质。当x = 0.02时，迁移率的理论值与实验值吻合良好；当x = 0.125时，迁移率的理论值与实验值吻合良好。对于迁移率的计算，考虑了声子散射（声子变形势、声子变形势、声子变形势、声子谷间散射）、合金无序、杂质以及电子-电子散射。

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引用次数: 0

High-performance photodetector based on hybrid 2D WSe2/Ag-in-Ga-S QDs heterojunction 基于混合二维WSe2/Ag-in-Ga-S量子点异质结的高性能光电探测器

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-12 DOI: 10.1016/j.physe.2025.116391

Jiahao Yang, Banqin Ruan, Zhentao Ke, Jiahao Zhang, Yiyang An, Zixuan Guo, Zhi Li, Xiufeng Song, Haibo Zeng

Two-dimensional (2D) materials have emerged as a prominent research focus due to their excellent properties and broad application. Among these, tungsten diselenide (WSe₂), a representative transition-metal dichalcogenide (TMDC), exhibits high carrier mobility and a tunable band gap when reduced to a 2D structure, making it particularly attractive for electronic and optoelectronic applications. However, the inherent weak absorption in 2D materials remains a fundamental limitation. To address this challenge, we developed a heterojunction photodetector by integrating Ag-In-Ga-S (AIGS) quantum dots (QDs) with 2D WSe₂. The device combines the superior high carrier mobility of 2D materials with the strong light-harvesting capability of quantum dots, facilitating efficient photogenerated carrier separation and enhanced photocurrents, thereby improving photoresponse performance. The obtained heterojunction demonstrates extraordinary optoelectronic performance, achieving a responsivity of 1.81 × 10⁴ A/W, a detectivity of 1.3 × 10¹³ Jones and an external quantum efficiency of 4.27 × 10⁵ %. These results indicate the significant potential of 2D materials/QDs hybrid systems for advanced photodetector applications.

二维（2D）材料由于其优异的性能和广泛的应用而成为一个突出的研究热点。其中，二硒化钨（WSe2）是一种代表性的过渡金属二硫族化合物（TMDC），当还原为二维结构时，具有高载流子迁移率和可调带隙，使其在电子和光电子应用中特别具有吸引力。然而，二维材料固有的弱吸收仍然是一个基本的限制。为了解决这一挑战，我们通过将Ag-In-Ga-S （AIGS）量子点（QDs）与2D WSe2集成开发了一种异质结光电探测器。该器件结合了二维材料优越的高载流子迁移率和量子点强大的光捕获能力，促进了高效的光生载流子分离和增强的光电流，从而提高了光响应性能。得到的异质结具有优异的光电性能，响应率为1.81 × 104 a /W，探测率为1.3 × 1013 Jones，外量子效率为4.27 × 105%。这些结果表明了二维材料/量子点混合系统在先进光电探测器应用中的巨大潜力。

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引用次数: 0

Two-dimensional high-temperature magnetic MoNX2 (X = F, Cl, Br, I) with piezoelectricity, ferroelectricity, and optical anisotropy 具有压电性、铁电性和光学各向异性的二维高温磁性MoNX2 （X = F, Cl, Br， I）

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-10 DOI: 10.1016/j.physe.2025.116389

Wen-Zhi Xiao, Gang Xiao, Hai-Qing Xu, Xin-Hua Gao, Jun He

Two-dimensional (2D) multifunctional materials with distinctive features such as magnetic, ferroelectric, piezoelectric, and optical property are in high demand due to their potential applications in novel nanoscale devices. Herein, based on first-principles calculations, we present a family of 2D multiferroic MoNX₂ (X = F, Cl, Br, I) materials. Among them, MoNF₂ is an anti-ferroelectric (AFE) ferromagnetic (FM) semiconductor with Curie temperature (T_C) of 497 K. MoNX₂ (X = Cl, Br) are ferroelectric (FE) antiferromagnetic (AFM) semiconductors. All of them exhibit an in-plane spontaneous electric polarization of up to 260 pC m⁻¹ and piezoelectric response. The FE switching energy barrier is no more than 0.1 eV per atom for them. Additionally, they exhibit strong linear optical dichroism and hyperbolicity in the visible light region. The alignments of the band edges of MoNX₂ (X = Cl, Br, I) with the redox potentials of water show that these materials are suitable for use as photocatalysts for water splitting. Their intriguing magnetic, electronic, ferroelectric, piezoelectric and optical properties render them ideal for use in high-performance, multifunctional applications.

二维（2D）多功能材料具有磁性、铁电性、压电性和光学性等独特的特征，由于其在新型纳米级器件中的潜在应用，因此需求量很大。在此，基于第一性原理计算，我们提出了一类二维多铁性MoNX2 （X = F, Cl, Br， I）材料。其中MoNF2是一种反铁电（AFE）铁磁（FM）半导体，居里温度（TC）为497 K。MoNX2 （X = Cl, Br）是铁电（FE）反铁磁（AFM）半导体。它们都表现出高达260 pC m−1的面内自发电极化和压电响应。它们的FE开关能垒不大于0.1 eV /原子。此外，它们在可见光区表现出强烈的线性光学二色性和双曲性。MoNX2 （X = Cl, Br， I）的带边与水的氧化还原电位的排列表明，这些材料适合作为水裂解的光催化剂。它们迷人的磁性、电子性、铁电性、压电性和光学性使其成为高性能、多功能应用的理想选择。

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引用次数: 0

Manipulation of valley polarization and anomalous valley Hall effect in monolayer ferrovalley AgMoP2S6 单层铁谷AgMoP2S6中谷极化和异常谷霍尔效应的操纵

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-09 DOI: 10.1016/j.physe.2025.116387

Lan Luo , Xianjuan He , Wenzhe Zhou , Qinglin Xia , Fangping Ouyang

Due to the role of the valley as an information carriers, two-dimensional valleytronics materials have broad prospects in information storage in the future. However, materials with intrinsic valley polarization are rare. In our work, using first-principles calculations, we propose a valleytronics material monolayer (ML) AgMoP₂S₆ with a ferromagnetic(FM) ground state. The ferromagnetic exchange interaction breaks the time-reversal symmetry, which results in a spontaneous valley polarization of 78 meV at the K/-K points on the valence band under the action of strong SOC. The valley polarization can be tuned by biaxial strain and Hubbard U, and when the tensile strain exceeds 4 % and U exceeds 2 eV, valley polarization also appears in the conduction band. Under the action of an in-plane electric field, the breaking of valley degeneracy makes the appearance of anomalous valley Hall effect (AVHE) effect a possibility. ML AgMoP₂S₆ is an ideal valleytronics material.

由于谷作为信息载体的作用，二维谷电子材料在未来的信息存储方面具有广阔的前景。然而，具有本征谷极化的材料是罕见的。在我们的工作中，使用第一性原理计算，我们提出了一种具有铁磁基态的谷电子材料单层（ML） AgMoP2S6。铁磁交换作用打破了时间反转对称性，在强荷电性作用下，在价带K/-K点产生了78 meV的自发谷极化。双轴应变和Hubbard U可以调节谷极化，当拉伸应变超过4%，U超过2 eV时，导带也出现谷极化。在面内电场作用下，谷简并的破缺使反常谷霍尔效应（AVHE）的出现成为可能。AgMoP2S6是一种理想的谷电子材料。

引用次数: 0

Anomalous Seebeck effect in non-Hermitian double quantum dots 非厄米双量子点中的反常塞贝克效应

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-09 DOI: 10.1016/j.physe.2025.116385

Pengbin Niu , Li Xu , Hui Yao , Hong-Gang Luo

We investigate the thermoelectrical transport in a system of non-Hermitian double quantum dots. For that purpose, we set up a model where two quantum dots are experiencing gain and loss of energy and in proximity to two superconductors. By applying Keldysh Green’s function technique, we study the transmission function, conductance as well as the Seebeck coefficient. We calculate the thermoelectric quantities both analytically and numerically and show that a sign change of the Seebeck coefficient can occur when electrons transport through the Andreev bound states forming on the quantum dots. The sign change is induced by the competition of superconducting pairing potential and PT-symmetric complex potential, when the system passes through the exceptional point. These findings may be attractive for the study of quantum thermoelectric effects.

研究了非厄米双量子点系统中的热电输运。为此，我们建立了一个模型，其中两个量子点正在经历能量的增益和损失，并且靠近两个超导体。应用Keldysh Green函数技术，研究了传输函数、电导和塞贝克系数。我们用解析法和数值法计算了热电量，并表明当电子通过量子点上形成的Andreev束缚态传输时，Seebeck系数会发生符号变化。当系统通过异常点时，符号变化是由超导偶势和pt对称复势的竞争引起的。这些发现对量子热电效应的研究具有重要意义。

引用次数: 0

Nonlinear corrections to the thermoelectric efficiency of a nanoscale device 纳米器件热电效率的非线性修正

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-08 DOI: 10.1016/j.physe.2025.116383

Raymond J. Hartig , Ioan Grosu , Ionel Ţifrea

<div><div>We investigate the nonlinear thermoelectric transport in a generic nanoscale device connected to two side reservoirs at different temperatures (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>L</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span>) and chemical potentials (<span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>L</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span>). We derive equations for the charge (electric) and heat (thermal) currents. These equations allow for the estimation of the second order contributions to the system’s thermoelectric response and the <em>analytical</em> derivation of the first nonlinear contributions to the system’s electric conductance <span><math><msup><mrow><mi>σ</mi></mrow><mrow><mrow><mo>(</mo><mn>2</mn><mo>)</mo></mrow></mrow></msup></math></span>, Seebeck coefficient <span><math><msup><mrow><mi>S</mi></mrow><mrow><mrow><mo>(</mo><mn>2</mn><mo>)</mo></mrow></mrow></msup></math></span>, and electronic thermal conductance <span><math><msubsup><mrow><mi>κ</mi></mrow><mrow><mi>e</mi><mi>l</mi></mrow><mrow><mrow><mo>(</mo><mn>2</mn><mo>)</mo></mrow></mrow></msubsup></math></span>. In the generation mode, when the system’s output power is positive (<span><math><mrow><mi>P</mi><mo>></mo><mn>0</mn></mrow></math></span>), we estimate the maximum output power and efficiency of the system. The results are general and rely on generic dimensionless kinetic transport coefficients <span><math><mrow><msubsup><mrow><mi>K</mi></mrow><mrow><mi>n</mi></mrow><mrow><mi>p</mi></mrow></msubsup><mrow><mo>(</mo><mi>μ</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> that depends on the system’s characteristic electronic transmission function <span><math><mrow><mi>τ</mi><mrow><mo>(</mo><mi>E</mi><mo>)</mo></mrow></mrow></math></span>. To outline the differences between the linear and nonlinear approximations we consider the particular case of a generalized Fano line-shape electronic transmission function and exactly calculate the dimensionless kinetic transport coefficients in terms of Hurwitz zeta functions and Bernoulli numbers. The output power efficiency of the system is estimated as function of the energy <span><math><mrow><mi>ɛ</mi><mo>=</mo><mrow><mo>(</mo><msub><mrow><mi>E</mi></mrow><mrow><mi>d</mi></mrow></msub><mo>−</mo><mi>μ</mi><mo>)</mo></mrow><mo>/</mo><msub><mrow><mi>k</mi></mrow><mrow><mi>B</mi></mrow></msub><mi>T</mi></mrow></math></span> and broadening <span><math><mrow><mi>γ</mi><mo>=</mo><msub><mrow><mi>Γ</mi></mrow><mrow><mi>d</mi></mrow></msub><mo>/</mo><msub><mrow><mi>k</mi></mrow><mrow><mi>B</mi></mrow></msub><mi>T</mi></mrow></math></span> parameters. These results support the need for higher order terms in the theoretical analysis of the thermoelectric transport in nanoscale devices and allow for the optimization of the system’s propert

我们研究了在不同温度（TL和TR）和化学势（μL和μR）下连接两个侧储层的通用纳米器件的非线性热电输运。我们推导出电荷（电）流和热（热）流的方程。这些方程允许对系统热电响应的二阶贡献进行估计，并对系统电导σ(2)、塞贝克系数S(2)和电子热导κel(2)的一阶非线性贡献进行解析推导。在发电模式下，当系统的输出功率为正（P>0）时，我们估计系统的最大输出功率和效率。结果具有普遍性，依赖于依赖于系统特征电子传输函数τ(E)的一般无因次动力学输运系数Knp（μ，T）。为了概述线性近似和非线性近似的区别，我们考虑了广义法诺线形电子传输函数的特殊情况，并精确计算了基于Hurwitz zeta函数和伯努利数的无因次动力学传输系数。系统的输出功率效率估计为能量=(Ed−μ)/kBT和展宽γ=Γd/kBT参数的函数。这些结果支持在纳米级器件热电输运的理论分析中需要高阶项，并允许优化系统特性以获得有效的热电响应。

引用次数: 0

Voltage fluctuations in a four-terminal quantum device with orthogonal, unitary or symplectic symmetry 正交对称、酉对称或辛对称的四端量子器件中的电压波动

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-10-08 DOI: 10.1016/j.physe.2025.116386

F. Castañeda-Ramírez , M. Martínez-Mares , A.M. Martínez-Argüello

The statistical fluctuations of the voltage across a quantum wire in a four-terminal arrangement, where two of the terminals are used as probes while the other two are used to establish a flux current, is studied in the single channel case. The quantum wire to be measured consists of a chaotic microcavity or a disordered conductor in the presence of one of the three symmetry classes: orthogonal, unitary, or symplectic. Using the circular ensembles of random matrix theory or the Dorokov–Mello–Pereyra–Kumar (DMPK) equation, the statistical distribution of the voltage is reduced to quadratures for noninvasive probes which is solved numerically. Numerical simulations from random matrix theory or for the DMPK equation are performed for any coupling strength of the probes. For the chaotic cavity the effect of the symmetry class is clearly manifested through the weak and weak anti-localization phenomena for the orthogonal and symplectic symmetry classes, respectively. A similar effect is found, but with respect to the degree of disorder in a quantum wire as it evolves from strong to weak disorder: a simple correspondence between the label of the symmetry class and the degree of disorder, is found.

在单通道情况下，研究了四端排列中电压的统计波动，其中两个终端用作探针，而另外两个用于建立磁通电流。要测量的量子线由一个混沌微腔或无序导体组成，其中存在三种对称类：正交、酉或辛。利用随机矩阵理论的圆系综或Dorokov-Mello-Pereyra-Kumar （DMPK）方程，将无创探头的电压统计分布简化为正交分布，并进行数值求解。利用随机矩阵理论或DMPK方程对任意耦合强度的探针进行了数值模拟。对于混沌腔，对称类的影响通过正交对称类和辛对称类的弱和弱反局域化现象清晰地表现出来。发现了类似的效应，但是是关于量子线从强无序到弱无序的程度：发现了对称类的标签和无序程度之间的简单对应关系。

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引用次数: 0

Quantum Hall-like effect for neutral particles with magnetic dipole moments in a quantum dot 量子点中具有磁偶极矩的中性粒子的量子霍尔效应

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-30 DOI: 10.1016/j.physe.2025.116381

Carlos Magno O. Pereira, Edilberto O. Silva

We predict a new class of quantum Hall phenomena in completely neutral systems, demonstrating that the interplay between radial electric fields and dipole moments induces exact

e^{2} / h

quantization without Landau levels or external magnetic fields. Contrary to conventional wisdom, our theory reveals that: (i) the singularity of line charges does not destroy topological protection, (ii) spin control of quantization emerges from boundary conditions alone, and (iii) the effect persists up to 25 K, surpassing typical neutral systems. These findings establish electric field engineering as a viable route to topological matter beyond magnetic paradigms.

我们在完全中性系统中预测了一类新的量子霍尔现象，证明了径向电场和偶极矩之间的相互作用在没有朗道能级或外部磁场的情况下诱导了精确的e2/h量子化。与传统观点相反，我们的理论揭示：(i)线电荷的奇点不会破坏拓扑保护，（ii）量子化的自旋控制仅来自边界条件，以及（iii）效应持续到25 K，超过典型的中性系统。这些发现确立了电场工程作为超越磁范式的拓扑物质的可行途径。

引用次数: 0

Strain-engineered electronic and thermoelectric properties of ZrX2 (X=S, Se) monolayers: A first-principles study ZrX2 （X=S, Se）单层的应变工程电子和热电性质：第一性原理研究

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

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2025-09-30 DOI: 10.1016/j.physe.2025.116384

Khatir Ouail, Samia Ferahtia, Salima Saib, Nadir Bouarissa

Through comprehensive first-principles calculations coupled with Boltzmann transport theory, we systematically investigate the strain-dependent structural, mechanical, electronic, and thermoelectric properties of monolayer ZrX₂ (X = S, Se). Our mechanical analysis reveals both materials maintain exceptional stability under biaxial strains ranging from −10 % to +10 %, with ZrS₂ exhibiting superior mechanical robustness as evidenced by its higher Young's modulus (73.95 N/m) compared to ZrSe₂ (63.70 N/m). Detailed electronic structure calculations employing the TB-mBJ potential demonstrate these monolayers are indirect band gap semiconductors, with fundamental gaps of 1.8 eV for ZrS₂ and 1.16 eV for ZrSe₂. Notably, compressive strain induces dramatic electronic transitions, reducing the band gap progressively until ZrSe₂ undergoes a complete semiconductor-to-metal transition at −10 % strain. The thermoelectric transport properties show remarkable strain sensitivity. Applied biaxial strain enhances the power factor by an order of magnitude, reaching exceptional values of 2.4 × 10¹¹ W/mK²s for ZrSe₂ at −6 % strain. Comparative analysis reveals n-type doping consistently outperforms p-type configurations in thermoelectric efficiency across all strain conditions. These enhancements originate from strain-induced modifications to both electronic band structures and carrier scattering mechanisms. Our combined mechanical, electronic, and thermoelectric characterization provides fundamental insights into the strain-response of ZrX₂ monolayers, demonstrating their exceptional tunability for next-generation flexible electronics, strain sensors, and high-efficiency energy conversion devices. The comprehensive dataset presented here establishes a foundation for future experimental investigations and device applications of these promising 2D materials.

通过综合第一性原理计算和玻尔兹曼输运理论，我们系统地研究了单层ZrX2 （X = S, Se）的应变相关结构、力学、电子和热电性质。我们的力学分析表明，两种材料在- 10%至+ 10%的双轴应变范围内都保持了出色的稳定性，ZrS2表现出优异的机械鲁棒性，与ZrSe2 （63.70 N/m）相比，ZrSe2的杨氏模量（73.95 N/m）更高。利用TB-mBJ电位的详细电子结构计算表明，这些单层是间接带隙半导体，ZrS2的基本隙为1.8 eV， ZrSe2的基本隙为1.16 eV。值得注意的是，压缩应变引起了剧烈的电子跃迁，逐渐减小了带隙，直到ZrSe2在- 10%应变下经历了完全的半导体到金属的跃迁。热电输运性能表现出显著的应变敏感性。施加双轴应变使功率因数提高了一个数量级，ZrSe2在- 6%应变下达到2.4 × 1011 W/mK2s的异常值。对比分析表明，在所有应变条件下，n型掺杂的热电效率始终优于p型掺杂。这些增强源于应变诱导的电子能带结构和载流子散射机制的修改。我们结合了机械、电子和热电特性，为ZrX2单层的应变响应提供了基本的见解，展示了它们在下一代柔性电子、应变传感器和高效能量转换设备上的卓越可调性。这里提出的综合数据集为这些有前途的二维材料的未来实验研究和设备应用奠定了基础。

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引用次数: 0