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近年来，极性磁体M2Mo3O8(M：3d过渡金属)因其独特的晶体结构、多重连续的磁电耦合态转变及潜在应用价值，成为凝聚态物理和材料科学领域的研究热点。特别是Co2Mo3O8基态下展现出显著的二阶非线性磁电耦合效应，对应独特的磁电耦合微观机制和实际应用价值。本文基于分子场唯象模型，构建了Co2Mo3O8体系的两套不同的反铁磁子格子，给出体系的自发磁矩、自旋诱导的铁电极化、一阶线性磁电耦合系数、以及二阶非线性磁电耦合系数随温度的变化关系。结果显示Co2Mo3O8的二阶磁电耦合系数要明显比同构的Fe2Mo3O8以及Mn2Mo3O8大，这主要是因为Co2Mo3O8的两个不同子格子间的反铁磁交换作用能量更低，体系所处的状态更加稳定。这也表明，在Co2Mo3O8体系拥有更加稳定的不可逆性，展现了非常明显的磁电二极管(magnetoelectric diode)效应，为磁电二极管(magnetoelectric diode)的发展提供了坚实的理论和实验基础。In recent years, polar magnets M2Mo3O8(M:3d transition metal) have emerged as a research focus in condensed matter physics and materials science due to their unique crystal structures, multiple continuous magnetoelectric-coupled state transitions, and potential applications. Notably, Co2Mo3O8 exhibits a significant second-order nonlinear magnetoelectric coupling effect in its ground state, corresponding to a unique microscopic magnetoelectric coupling mechanism and practical value. In this work, based on a molecular field phenomenological model, we construct two distinct antiferromagnetic sublattices for the Co2Mo3O8 system and present the temperature-dependent variations of its spontaneous magnetic moment, spin-induced ferroelectric polarization, first-order linear magnetoelectric coupling coefficient, and second-order nonlinear magnetoelectric coupling coefficient. Particularly, the parameters t=-1 and o=-0.96 indicate distinct exchange energies between the magnetic sublattices associated with tetrahedra (Cot) and octahedra (Coo). The Co2+ ions in these two sublattices, which were characterized by different molecular field coefficients, synergistically mediate a spin-induced spontaneous polarization of PS~0.12 μC/cm2 through the exchange striction mechanism and p-d hybridization mechanism in Co2Mo3O8. In addition, the significant second-order magnetoelectric coupling effect with a coefficient peaking at 70x10-19 s/A near the TN in Co2Mo3O8, where this coefficient is significantly larger than those of isostructural Fe2Mo3O8 (1.81x10-28 s/A) and Mn2Mo3O8, implies that this enhancement primarily arises from the weaker inter-sublattice antiferromagnetic exchange between its two sublattices, leading to a stabilizes metastable spin configuration. This also indicates that the Co2Mo3O8 system possesses stronger irreversibility stability and exhibits a pronounced magnetoelectric diode effect, providing a solid theoretical and computational foundation for the development of magnetoelectric diodes.<
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Keywords:
- Magnetoelectric coupling effect /
- Multiferroicity /
- Polar magnet /
- Mean-field approximation
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[1] Kimura T, Goto T, Shintani H, Ishizaka K, Arima T, and Tokura Y 2003Nature 426 55
[2] Cheong S, Mostovoy M 2007Nat. Mater. 6 13
[3] Spaldin N, Ramesh R 2019Nat. Mater. 18 203.
[4] Lu C L, Wu M H, Lin L, Liu J -M 2019Nat. Sci. Rev. 6 653
[5] Dong S, Liu J -M, Cheong S -W, and Ren Z 2015Adv. Phys. 64 519
[6] Nan C W 2015Sci. Sin.: Tech. 45339(in Chinese) [南策文2015中国科学: 技术科学45339]
[7] Liu J M, Nan C W 2014Physics 4388(in Chinese) [刘俊明, 南策文2014物理4388]
[8] Li Z W, Zhang S Y, Li Q S, and Liu H 2023J. Adv. Dielect. 13 2345002
[9] Liang M C, Yang J, Yang H Y, Liang C, Nie Z Y, Ai H, Zhang T, Ma J, Huang H B, and Wang J 2024J. Adv. Dielect. 14 2440002
[10] Khade V, and Wuppulluri M 2024 J. Adv. Dielect. 14 2340001
[11] Wu F, Bao S, Zhou J, Wang Y, Sun J, Wen J, Wan Y, and Zhang Q 2023Nat. Phys. 19 1868
[12] Wang J, Neaton J B, Zheng H, Nagarajan V, Ogale S B, Liu B, Viehland D, Vaithyanathan V, Schlom D G, Waghmare U V, Spldin N A, Rabe K M, Wuttig M, and Ramesh R 2003Science 299 1719
[13] Wang Y Z, Pascut G L, Gao B, Tyson T A, Haule K, Kiryukhin V, and Cheong S -W 2015Sci. Rep. 5 12268
[14] Spaldin N A, and Ramesh R 2019Nat. Mater. 18 203
[15] Kurumaji T, Ishiwata S, and Tokura Y 2015Phys. Rev. X 5 031034
[16] Chang Y, Weng Y, Xie Y, You B, Wang J, Li L, Liu J -M, Dong S, and Lu C 2023 Phys. Rev. Lett. 131 136701
[17] Tang Y, Wang S, Lin L, Li C, Zheng S, Li C, Zhang J, Yan Z, Jiang X, and Liu J -M 2019Phys. Rev. B 100 134112
[18] Kim J, Artyukhin S, Mun E, Jaime M, Harrison N, Hansen A, Yang J, Oh Y, Vanderbilt D, Zapf V, and Cheong S 2015Phys. Rev. Lett. 115 137201
[19] Rivera J -P 1994Ferroelectrics 161 165
[20] Kurumaji T, Ishiwata S, Tokura Y 2017Phys. Rev. B 95 045142
[21] Kurumaji T, Takahashi Y, Fujioka J, Masuda R, Shishikura H, Ishiwata S, and Tokura Y 2017Phys. Rev. B 95020405(R)
[22] Yu B, Hu Z -Q, Cheng Y -X, Peng B, Zhou Z -Y, Liu M 2018 Acta Phys. Sin. 67 157507(in Chinese) [俞斌, 胡忠强, 程宇心, 彭斌, 周子尧, 刘明2018物理学报67 157507]
[23] Shen J, Shang D, Sun Y 2018Acta Phys. Sin. 67 127501(in Chinese) [申见昕, 尚大山, 孙阳2018物理学报67 127501]
[24] Yu S, Gao B, Kim J, Cheong S -W, Man M, Madéo J, Dani K, and Talbayev D 2018Phys. Rev. Lett. 120 037601
[25] Tang Y, Zhou G, Lin L, Chen R, Wang J, Lu C, Huang L, Zhang J, Yan Z, Lu X, Huang X, Jiang, and Liu J -M 2022 Phys. Rev. B 105064108
[26] Reschke S, Farkas D, Strinić A, Ghara S, Guratinder K, Zaharko O, Prodan L, Tsurkan V, Szaller D, Bordács S, Deisenhofer J, and Kézsmárki I 2022npj Quantum Mater. 7 1
[27] McAlister S, and Strobel P 1983J. Magn. Magn. 30 340
[28] Tang Y, Zhang J, Lin L, Chen R, Wang J, Zheng S, Li C, Zhang Y, Zhou G, Huang L, Yan Z, Lu X, Wu D, Huang X, Jiang X, and Liu J -M 2021Phys. Rev. B 103 014112
[29] Schmid H 1973Int. J. Magn. 4 337
[30] Johnston D, McQueeney R, Lake B, Honecker A, Zhitomirsky M, Nath R, Furukawa Y, Antropov V, and Yogesh Singh 2011Phys. Rev. B 84 094445
[31] Solovyev I V, Streltsov S V 2019Phys. Rev. Matter. 3 114402
[32] Taniguchi K, Abe N, Takenobu T, Iwasa Y, and T. Arima 2006Phys. Rev. Lett. 97 097203
[33] Balents L 2010 Nature 464 199
[34] Joshua S J 1984Aust. J. Phys. 37 305
[35] Dou S, Yang X, Xia Y, Yuan J, Cui H, Wei B, Bai X, Feng C 2023Acta Phys. Sin. 72157501(in Chinese) [豆树清, 杨晓阔, 夏永顺, 袁佳卉, 崔焕卿, 危波, 白馨, 冯朝文2023物理学报72 157501]
[36] Song X, Gao X, Liu J -M 2018Acta Phys. Sin. 67 157512(in Chinese) [宋骁, 高兴森, 刘俊明2018物理学报67 157512]
[37] Tang Y, Zhou S, Weng Y, Zhang A, Zhang Y, Zheng S, and Li X 2025 Phys. Rev. B 111 134423
[38] Wei X, Zhang X, Yu H, Gao L, Tang W, Hong M, Chen Z, Kang Z, Zhang Z, and Zhang Y 2024Nat. Electr. 7 138
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