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针对高速电子器件与光电器件的发展需求, 探索并设计具有优异载流子输运特性的二维半导体材料已成为该领域的核心科学问题. 本文基于密度泛函理论, 采用第一性原理计算系统地探究了面内应力对单层FeGa2S4材料输运性质及光学性质的调控规律. 结果表明, FeGa2S4易于剥离, 其单层结构具有较好的动力学、热力学稳定性和面内各向同性的机械性能, 较低的杨氏模量使其在外部应力下易于形变. 与母相块材相似, 单层FeGa2S4也是一种间接带隙半导体(能隙为1.65 eV), 在单轴应力(应变范围±5%)调控下, 空穴迁移率基本保持不变(约103 cm2·V−1·s–1), 电子迁移率(+5%应变)则提升超过一个数量级. 双轴拉伸应力则能够有效提升材料在可见光范围内的光捕获能力. 研究结果表明单层FeGa2S4在高速电子和柔性光电器件领域具有较大的应用前景.This study aims to explore two-dimensional semiconductor materials with superior carrier transport properties to meet the growing demands of high-speed electronics and optoelectronic devices, focusing on evaluating the feasibility of monolayer FeGa2S4 as a candidate material through systematic theoretical investigations. First-principles calculations are used to analyze the exfoliation energy of FeGa2S4 bulk crystal, as well as the structural stability, mechanical properties, and strain-dependent optoelectronic behavior of its monolayer counterpart. Strain engineering strategies, including uniaxial and biaxial strain, are used to assess carrier mobility modulation and spectral response. Our calculation results indicate that monolayer FeGa2S4 is an indirect bandgap semiconductor (Eg = 1.65 eV) with low stiffness (Young’s modulus up to 151.6 GPa) and high flexibility (Poisson’s ratio less than 0.25), demonstrating exceptional thermodynamic stability. Under +5% uniaxial tensile strain, its electron mobilities along x and y directions dramatically increases to 5402.4 cm2·V–1·s–1 and 4164.0 cm2·V–1·s–1, fivefold higher than its hole mobility. Biaxial strain outperforms uniaxial strain in bandgap modulation and induces a systematic redshift in optical spectra, significantly enhancing visible-light harvesting efficiency. This work reveals that monolayer FeGa2S4 is a promising high-mobility photoactive material for next-generation solar cells and optoelectronics. The strain-mediated control of electronic and optical properties provides a theoretical framework for optimizing 2D semiconductors and critical guidance for experimental synthesis and device engineering. These findings highlight the potential of materials in advancing energy conversion technology and photonic applications.
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Keywords:
- first-principles /
- electronic structure /
- optical properties /
- strain engineering
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图 1 (a) 体相FeGa2S4晶体结构的侧视图, 黑框内为其块材的一个原胞; (b) FeGa2S4的剥离能
Fig. 1. (a) Side view of FeGa2S4 bulk, its primitive cell is marked with a black frame; (b) the exfoliation energy of FeGa2S4
图 2 单层FeGa2S4的结构示意图 (a) 俯视图; (b) 侧视图; (c) 单胞的声子谱; (d) 3×3×1超晶胞结构分子动力学模拟
Fig. 2. (a) Top and (b) side views of FeGa2S4 monolayer, (c) phonon dispersion curves of FeGa2S4 monolayer unit cell; (d) evolution of total energy and snapshots of FeGa2S4 monolayer 3×3×1 supercell from AIMD simulations.
图 3 FeGa2S4单层面内杨氏模量(a)和泊松比(b)
Fig. 3. Young’s moduli (a) and Poisson’s ratio (b) of FeGa2S4 monolayer.
图 5 (a) x和y输运方向的定义; (b) 单层FeGa2S4的载流子迁移率应变响应特性
Fig. 5. (a) Definition of transport directions x and y; (b) carrier mobility of monolayer FeGa2S4 under uniaxial strain.
图 6 单层FeGa2S4超胞的导带底局域电荷密度示意图及轨道投影能带图
Fig. 6. Partial charge densities of the conduction band minimum and projected band structure of FeGa2S4 monolayer supercell.
图 7 单层FeGa2S4带隙随面内单双轴应变变化曲线
Fig. 7. Variation of band gap of FeGa2S4 monolayer with various in-plane strain.
图 8 双轴应变ε = 0%, ε = ±3%和ε = +5%时, 单层FeGa2S4的吸收率、反射率和透射率
Fig. 8. Absorption, reflectance and transmission of monolayer FeGa2S4 under ε = 0%, ε = ±3% and ε = +5% biaxial strain.
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[1] Novoselov K S, Geim A K, Morozov S V, Jiang D, Zhang Y, Dubonos S V, Grigorieva I V, Firsov A A 2004 Science 306 666
Google Scholar
[2] Banszerus L, Schmitz M, Engels S, Dauber J, Oellers M, Haupt F, Watanabe K, Taniguchi T, Beschoten B, Stampfer C 2015 Sci. Adv. 1 e1500222
Google Scholar
[3] Lee C, Wei X D, Kysar J W, Hone J 2008 Science 321 385
Google Scholar
[4] Balandin A A, Ghosh S, Bao W Z, Calizo I, Teweldebrhan D, Miao F, Lau C N 2008 Nano Lett. 8 902
Google Scholar
[5] Berger C, Song Z M, Li T B, Li X B, Ogbazghi A Y, Feng R, Dai Z T, Marchenkov A N, Conrad E H, First P N, de Heer W A 2004 J. Phys. Chem. B 108 19912
Google Scholar
[6] Liu M, Yin X B, Ulin-Avila E, Geng B S, Zentgraf T, Ju L, Wang F, Zhang X 2011 Nature 474 64
Google Scholar
[7] Withers F, Dubois M, Savchenko A K 2010 Phys. Rev. B 82 073403
Google Scholar
[8] Liu B, Zhou K 2019 Prog. Mater. Sci. 100 99
Google Scholar
[9] Cai Y Q; Zhang G, Zhang Y W 2014 Sci. Rep. 4 6677
Google Scholar
[10] Dean C R, Young A F, Meric I, Lee C, Wang L, Sorgenfrei S, Watanabe K, Taniguchi T, Kim P, Shepard K L, Hone J 2010 Nat. Nanotechnol. 5 722
Google Scholar
[11] Bandurin D A, Tyurnina A V, Yu G L, Mishchenko A, Zólyomi V, Morozov S V, Kumar R K, Gorbachev R V, Kudrynskyi Z R, Pezzini S, Kovalyuk Z D, Zeitler U, Novoselov K S, Patanè A, Eaves L, Grigorieva I V , Fal’ko V I, Geim A K, Cao Y 2017 Nat. Nanotechnol. 12 223
[12] Hu P A, Wang L F, Yoon M, Zhang J, Feng W, Wang X N, Wen Z Z, Idrobo J C, Miyamoto Y, Geohegan D B, Xiao K 2013 Nano Lett. 13 1649
Google Scholar
[13] Chhowalla M, Shin H S, Eda G, Li L J, Loh K Ping, Zhang H 2013 Nat. Chem. 5 263
Google Scholar
[14] Ataca C, Sahin H, Ciraci S 2012 J. Phys. Chem. C 116 8983
Google Scholar
[15] Song Y, Pan J B, Zhang Y F, Yang H T, Du S X 2021 J. Phys. Chem. Lett. 12 6007
Google Scholar
[16] Zhang S L, Xie M Q, Li F Y, Yan Z, Li Y F, Kan E, Liu W, Chen Z F, Zeng H B 2016 Angew. Chem. Int. Ed. 55 1666
Google Scholar
[17] Guo Z L, Zhou J, Zhua L G, Sun Z M 2016 J. Mater. Chem. A 4 11446
Google Scholar
[18] 宋蕊, 王必利, 冯凯, 王黎, 梁丹丹 2022 71 037101
Google Scholar
Song R, Feng K, Wang B L, Wang L, Liang D D 2022 Acta Phys. Sin. 71 037101
Google Scholar
[19] Du Z G, Yang S B, Li S M, Lou J, Zhang S Q, Wang S, Li B, Gong Y J, Song L, Zou X L, Ajayan P M 2020 Nature 577 492
Google Scholar
[20] Kim Y, Woo W J, Kim D, Lee S, Chung S M, Park J, Kim H 2021 Adv. Mater. 33 2005907
Google Scholar
[21] Rong C, Su T, Li Z K, Chu T S, Zhu M L, Yan Y B, Zhang B W, Xuan F Z 2024 Nat. Commun. 15 1566
Google Scholar
[22] Victorin J, Razpopov A, Higo T, Dziobek-Garrett R, Kempa T J, Nakatsuji S, Valentí R, Drichko N 2024 Sci. Rep. 14 28040
Google Scholar
[23] Dogguy-Smiri L, Dung N H, Pardo M P 1980 Mater. Res. Bull. 15 861
Google Scholar
[24] Kresse G, Furthmuller J 1996 Phys. Rev. B 54 11169
Google Scholar
[25] Perdew J P, Burke K, Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
Google Scholar
[26] Monkhorst H J, Pack J D 1976 Phys. Rev. B 13 5188
Google Scholar
[27] Gonze X, Lee C 1997 Phys. Rev. B 55 10355
Google Scholar
[28] Sharan A, Sajjad M, Singh D J, Singh N 2022 Phys. Rev. Mater. 6 094005
Google Scholar
[29] Grimme S 2006 J. Comput. Chem. 27 1787
Google Scholar
[30] Gonze X, Lee C 1997 Phys. Rev. B 55 10355
Google Scholar
[31] Togo A, Tanaka I 2015 Scr. Mater. 108 1
Google Scholar
[32] Myoung B R, Kim S J, Kim C S 2008 J Korean Phys. Soc. 53 750
Google Scholar
[33] Zacharia R, Ulbricht H, Hertel T 2004 Phys. Rev. B 69 155406
Google Scholar
[34] Pavone P, Karch K, Schiitt O, Strauch D, Windl W, Giannozzi P, Baroni S 1993 Phys. Rev. B 48 3156
Google Scholar
[35] Mouhat F, Coudert F X 2014 Phys. Rev. B 90 224104
Google Scholar
[36] Cadelano E, Palla P L, Giordano S, Colombo L 2010 Phys. Rev. B 82 235414
Google Scholar
[37] Huang Z, Lu N, Wang Z F, Xu S H, Guan J, Hu Y W 2022 Nano Lett. 22 7734
Google Scholar
[38] Bardeen J, Shockley W 1950 Phys. Rev. 80 72
Google Scholar
[39] Xia F N, Wang H, Xiao D, Dubey M, Ramasubramaniam A 2014 Nat. Photonics 8 899
Google Scholar
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