Development of DFT-Based Spin-Orbit Torque Calculations in Magnetic Heterostructures

以作者查詢圖書館館藏

、以作者查詢臺灣博碩士

、以作者查詢全國書目

、勘誤回報

、線上人數：61

、訪客IP：18.191.210.100

姓名

黃寶輝(Bao-Huei Huang) 查詢紙本館藏

畢業系所

物理學系

論文名稱

(Development of DFT-Based Spin-Orbit Torque Calculations in Magnetic Heterostructures)

相關論文

★ Stretching effect on the spin transport properties of single molecular junctions: A first-principle study	★ First-principles study in wurtzite InN bulk, thin film, and nanobelt
★ The interfacial effect on spin-transfer torque in single molecular magnetic junctions: A first-principles study	★ Spin transport calculation for thiol-ended single-molecule magnetic junction
★ Combined first-principles and tight-binding Hamiltonian study of Fe-MgO-Fe magnetic tunnel junctions	★ Anchoring Effect on Spin Transport in Amine-Ended Single-Molecule Magnetic Junctions: A First-Principles Study
★ Analytic derivation for spin-transfer properties in magnetic tunnel junctions	★ Simulation for Cu-platted Front Side Metallization of Si-based Solar Cell
★ 利用單能階緊密鍵結模型計算磁性穿隧接合的自旋傳輸特性	★ Electronic and Spin Transport Properties of Fe/MgO/Fe Magnetic Tunnel Junction: Combined First-Principles Calculation and TB-NEGF Method
★ First-principles study in structural and elec-tronic properties of FeBaTiO3Fe multiferroic tunneling junction	★ Effect of contact geometry on the spin transfer calculation in amine-ended single-molecule magnetic junctions
★ Spin Transport Properties in Magnetic Heterojunctions: Analytical derivation in Green’s function and Multi-reflection process	★ Modification of Distributional Exact Diagonalization Approach for Single Impurity Anderson Model
★ Strain-Induced Magnetic-Nonmagnetic Transition in PtSe2 Nanoribbon: A First-Principles Study	★ 具電阻切換行為之氧化鋁磁性穿隧接面中低頻雜訊與傳輸機制研究

檔案

[Endnote RIS 格式]

[Bibtex 格式]

[相關文章]

[文章引用]

[完整記錄]

[館藏目錄]

至系統瀏覽論文 (2026-6-30以後開放)

摘要(中)

在磁阻式隨機存取記憶體（magnetoresistive random-access memory，MRAM）的產業中，基於自旋轉移力矩（spin-transfer torque，STT）的STT-MRAM被提議為下一代記憶體裝置，因其具備高速的寫入和讀取性能以及低能耗。然而，直接通過元件的穿隧電流，可能因焦耳熱效應而降低其壽命。在另一方面，新提出的基於自旋軌道力矩（spin-orbit torque，SOT）的SOT-MRAM可能可以克服這一問題。與穿隧電流不同的是，通過重金屬的平面寫入電流在界面產生SOT效應，從而翻轉了自由層的磁化方向。

從理論的角度來看，我們旨在了解自旋力矩的機制，同時考慮材料的性質、磁性、自旋軌道耦合（spin-orbit coupling，SOC）和電控制。我們為此開發了「JunPy」程式，利用非平衡格林函數（nonequilibrium Green′s function，NEGF）方法，與基於第一原理的自洽哈密頓量，來計算零電壓狀態和電流誘導的STT和SOT效應。

在這篇論文中，我們研究四個系統來演示自旋力矩的計算：（1）單分子磁性異質接面（single-molecule magnetic junctions，SMMJs）；（2）Fe/MgO/Fe磁性穿隧異質接面（magnetic tunnel junction，MTJ）；（3）鐵薄膜；（4）新穎凡德瓦二維鐵磁異質接面，Cr3Te4/PtTe2。研究SMMJs和MTJs中的零電壓和電流產生的STT，使我們能夠研究exchange bias效應和電流驅動的磁翻轉。除了利用常見的能量計算法，零電壓的SOT有助於我們探索平面或垂直磁各向異性。最後，我們研究了Cr3Te4/PtTe2中的電流誘導的SOT和介面產生的Rashba效應，演示了使用二維鐵磁材料來設計室溫SOT-MRAM的潛力。這些研究為自旋力矩的機制和操控提供了重要的見解，推動下一代記憶體裝置的發展，並進一步突顯了二維鐵磁材料在實現高效且可靠的MRAM技術中的潛力。

摘要(英)

In the magnetoresistive random-access memory (MRAM) industry, spin-transfer torque (STT) based STT-MRAM has been proposed as a next-generation memory device because of its high-speed writing and reading processes and low energy consumption. However, the direct tunneling current passing through the device can reduce its lifetime due to Joule heating. On the other hand, the newly proposed spin-orbit torque (SOT) based SOT-MRAM may overcome this issue. Instead of a tunneling current, an in-plane writing current flowing through a heavy metal generates a SOT effect at the interface, rotating the magnetization direction of the magnetic free layer.

From a theoretical perspective, we aim to understand the mechanism of spin torques, considering material properties, magnetism, spin-orbit coupling (SOC), and electrical control. For this purpose, we developed the "JunPy" package to calculate STT and SOT using first-principles calculated self-consistent Hamiltonians with the nonequilibrium Green′s function (NEGF) method. This allows us to study both equilibrium and current-induced STT and SOT.

In this dissertation, we examine four systems to demonstrate spin torque calculations: (1) single-molecule magnetic junctions (SMMJs), (2) a conventional Fe/MgO/Fe magnetic tunnel junction (MTJ), (3) iron thin films, and (4) a novel van der Waals two-dimensional ferromagnetic (2DFM) heterojunction, Cr3Te4/PtTe2. Studying the equilibrium and current-induced STT in SMMJs and MTJs allows us to investigate the exchange bias effect and current-driven magnetization switching. The equilibrium SOT helps us exploring in-plane or perpendicular magnetic anisotropy beyond the energy method. Finally, we investigate the current-induced SOT and interfacial Rashba effect in Cr3Te4/PtTe2, demonstrating the potential for designing a room-temperature SOT-MRAM using 2DFM materials. These studies provide valuable insights into the mechanisms and control of spin torques, advancing the development of next-generation MRAM technology. Furthermore, our works highlight the potential of 2DFM materials in achieving efficient and reliable MRAM technology.

關鍵字(中)

★ 自旋軌道力矩
★ 第一原理計算
★ 磁性異質結構
★ 凡德瓦材料
★ 非平衡格林函數
★ JunPy

關鍵字(英)

★ Spin-orbit torque
★ First-principles calculation
★ Magnetic heterostructures
★ Van der Waals materials
★ NEGF
★ JunPy

論文目次

摘要 i
Abstract iii
誌謝 v
Contents vii
List of Figures xi
List of Tables xix
1 Introduction 1
1.1 Current-Driven Magnetic Recording 1
1.1.1 MRAM and Magnetoresistance Effect 1
1.1.2 STT-MRAM and SOT-MRAM 2
1.2 Physics of Spin Current and Spin Torque 3
1.2.1 Spin-Transfer Effect 3
1.2.2 Spin Hall Effect 4
1.2.3 Rashba-Edelstein Effect 5
1.3 Physics of Magnetization Dynamics 7
1.4 Outline of Dissertation 8
2 First-Principles Calculation 11
2.1 Many-Electron Problems 11
2.2 Hartree-Fock Method 12
2.3 Density Functional Theory (DFT) 15
2.3.1 Hohenberg-Kohn Theorems 15
2.3.2 Kohn-Sham Equations 18
2.3.3 Exchange-Correlation Energy Functionals 20
2.4 Pseudopotentials 23
3 Nonequilibrium Green′s Function Formalism (NEGF) 27
3.1 Problems in Quantum Transport 27
3.2 Green′s Function Formalism 29
3.2.1 Time Evolution of Wavefunction 30
3.2.2 Green′s Function Representation 30
3.3 One-Electron Systems 32
3.3.1 Local Density of States 32
3.3.2 Expectation Value and Density Matrix 34
3.3.3 Matrix Representation 35
3.4 Many-Electron Systems 38
3.4.1 Self-Energy and Dyson Equation for Equilibrium Systems 38
3.4.2 Keldysh Equation for Nonequilibrium Systems 40
3.4.3 Expectation Value and Density Matrix 42
3.4.4 Matrix Representation 43
3.5 Two-Probe Systems 44
3.5.1 Hamiltonians and Green′sFunctions. 44
3.5.2 CurrentandTransmission 48
3.5.3 NEGF-DFT in Nanodcal 50
4 Theory of Spin Dynamics and Spin Torques 51
4.1 Theoretical Formalism 51
4.1.1 System Hamiltonian Operator 51
4.1.2 Spin Continuity Equation 52
4.1.3 Dynamics of Local Magnetic Moments 54
4.1.4 Role of Spin Torque in Magnetic Dynamics 55
4.2 First-Principles Implementation 57
4.2.1 Localized Orbital Representation 57
4.2.2 NEGF Formalism 61
5 JunPy Examples 63
5.1 Combining Nanodcal Package (factory.nanodcal) 63
5.1.1 Carbon Chain (Part1) 63
5.1.2 Carbon Chain (Part2) 66
5.1.3 Graphene 71
5.2 Combining Tight-Binding Model (factory.stack) 73
5.2.1 Simple Metallic Chain 73
5.2.2 FM/I/FM Magnetic Tunnel Junction 77
6 Amine-Ended Single-Molecule Magnetic Junctions 81
6.1 Introduction 81
6.2 Computational Details 83
6.3 Results and Discussion 85
6.3.1 EB Effect with Equilibrium FLST Field: DFT+JunPy+LLG 85
6.3.2 Role of Linker and Strain in Equilibrium FLST Field: TB+JunPy 88
6.3.3 Current-Driven Magnetization Switching: DFT+JunPy+LLG 91
6.4 Summary 94
7 Fe/MgO/Fe Magnetic Tunnel Junction 97
7.1 Introduction 97
7.2 Computational Details 99
7.3 Results and Discussion 101
7.3.1 Current-Driven STT without SOC 101
7.3.2 Interfacial SOT and PMA at Equilibrium 104
7.3.3 Layer-Resolved Spin Torque 105
7.4 Summary 107
8 Spin-Orbit Torque and Interfacial Magnetic Anisotropy 109
8.1 Introduction 110
8.2 Computational Details 111
8.3 Results and Discussion 114
8.3.1 Comparison between MAE and SOT 114
8.3.2 Layer-Resolved SOT 115
8.4 Summary 117
9 Cr3Te4-Based van der Waals Heterojunctions 119
9.1 Introduction 119
9.2 Computational Details 122
9.3 Results and Discussion 123
9.3.1 Surface Magnetic Anisotropy 124
9.3.2 Band Structure and Spin Texture 124
9.3.3 Current-Induced Spin-Orbit Torque 127
9.3.4 LLG Simulation 132
9.4 Summary 135
10 Conclusions 137
A Miscellaneous 139
A.1 Exchange Spin Torque in the Form of Cross Product 139
A.2 Extracting Hamiltonian Components 140
A.3 Energy Integration of Equilibrium Part 141
A.3.1 Spin Torque 142
A.3.2 Spin Accumulation 143
Bibliography 145

參考文獻

[1] 黃寶輝、唐毓慧、蔡民雄, 第一原理計算方法介紹與自旋傳輸計算之應用, 物理雙月刊 43 (2021) 17–26. URL: http://lawdata.com.tw/tw/detail.aspx?no=446026.
[2] H. Kubota, A. Fukushima, K. Yakushiji, T. Nagahama, S. Yuasa, K. Ando, H. Maehara, Y. Nagamine, K. Tsunekawa, D. D. Djayaprawira, N. Watanabe, Y. Suzuki, Quantitative measurement of voltage dependence of spin-transfer torque in MgO-based magnetic tunnel junctions, Nature Physics 4 (2008) 37–41. doi:10.1038/nphys784.
[3] X. Han, X. Wang, C. Wan, G. Yu, X. Lv, Spin-orbit torques: Materials, physics, and devices, Applied Physics Letters 118 (2021) 120502. doi:10.1063/5.0039147.
[4] N. Locatelli, V. Cros, J. Grollier, Spin-torque building blocks, Nature Materials 13 (2013) 11–20. doi:10.1038/nmat3823.
[5] Y. Niimi, Y. Otani, Reciprocal spin hall effects in conductors with strong spin–orbit coupling: a review, Reports on Progress in Physics 78 (2015) 124501. doi:10.1088/0034-4885/78/12/ 124501.
[6] V.P.Amin,P.M.Haney,M.D.Stiles,Interfacialspin–orbittorques,JournalofAppliedPhysics 128 (2020) 151101. doi:10.1063/5.0024019.
[7] P. Giannozzi, Notes on pseudopotential generation, 2019. URL: https://www. quantum-espresso.org/wp-content/uploads/2022/03/pseudo-gen.pdf.
[8] M. Di Ventra, Electrical Transport in Nanoscale Systems, Cambridge University Press, 2008. doi:10.1017/cbo9780511755606.
[9] B.-H. Huang, C.-C. Chao, Y.-H. Tang, Thickness dependence of spin torque effect in Fe/MgO/Fe magnetic tunnel junction: Implementation of divide-and-conquer with first-principles calculation, AIP Advances 11 (2021) 015036. doi:10.1063/9.0000117.
[10] E. Y. Tsymbal, Ž. Igor, Spintronics Handbook: Spin Transport and Magnetism, Second Edition, CRC Press, 2019. doi:10.1201/9780429423079.
[11] J. E. Hirsch, Spin hall effect, Physical Review Letters 83 (1999) 1834–1837. doi:10.1103/ PhysRevLett.83.1834.
[12] J. Sinova, D. Culcer, Q. Niu, N. A. Sinitsyn, T. Jungwirth, A. H. MacDonald, Universal Intrinsic Spin Hall Effect, Physical Review Letters 92 (2004) 126603. doi:10.1103/physrevlett.92. 126603.
[13] J. Sinova, S. O. Valenzuela, J. Wunderlich, C. Back, T. Jungwirth, Spin hall effects, Reviews of Modern Physics 87 (2015) 1213–1260. doi:10.1103/revmodphys.87.1213.
[14] M. Tian, Y. Zhu, M. Jalali, W. Jiang, J. Liang, Z. Huang, Q. Chen, Z. Zeng, Y. Zhai, Two-dimensional van der waals materials for spin-orbit torque applications, Frontiers in Nanotechnology 3 (2021). doi:10.3389/fnano.2021.732916.
[15] K.-S. Lee, D. Go, A. Manchon, P. M. Haney, M. D. Stiles, H.-W. Lee, K.-J. Lee, Angular dependence of spin-orbit spin-transfer torques, Physical Review B 91 (2015) 144401. doi:10. 1103/PhysRevB.91.144401.
[16] H. Nakayama, Y. Kanno, H. An, T. Tashiro, S. Haku, A. Nomura, K. Ando, Rashba-Edelstein Magnetoresistance in Metallic Heterostructures, Physical Review Letters 117 (2016) 116602. doi:10.1103/physrevlett.117.116602.
[17] J. Z. Sun, Spin-current interaction with a monodomain magnetic body: A model study, Physical Review B 62 (2000) 570–578. doi:10.1103/physrevb.62.570.
[18] A. A. Timopheev, R. Sousa, M. Chshiev, L. D. Buda-Prejbeanu, B. Dieny, Respective influence of in-plane and out-of-plane spin-transfer torques in magnetization switching of perpendicular magnetic tunnel junctions, Physical Review B 92 (2015) 104430. doi:10.1103/physrevb.92. 104430.
[19] M. Born, R. Oppenheimer, Zur quantentheorie der molekeln, Annalen der Physik 389 (1927) 457–484. doi:10.1002/andp.19273892002.
[20] A. Peruzzo, J. McClean, P. Shadbolt, M.-H. Yung, X.-Q. Zhou, P. J. Love, A. Aspuru-Guzik, J. L. O’Brien, A variational eigenvalue solver on a photonic quantum processor, Nature Communications 5 (2014) 4213. doi:10.1038/ncomms5213.
[21] V. Fock, Näherungsmethode zur Lösung des quantenmechanischen Mehrkörperproblems, Zeitschrift für Physik 61 (1930) 126–148. doi:10.1007/bf01340294.
[22] V.Fock,”Selfconsistentfield”mitAustauschfürNatrium,ZeitschriftfürPhysik62(1930)795– 805. doi:10.1007/bf01330439.
[23] R. M. Martin, Electronic Structure: Basic Theory and Practical Methods, Cambridge University Press, 2004. doi:10.1017/cbo9780511805769.
[24] P. Hohenberg, W. Kohn, Inhomogeneous electron gas, Physical Review 136 (1964) B864–B871. doi:10.1103/physrev.136.b864.
[25] W. Kohn, L. J. Sham, Self-consistent equations including exchange and correlation effects, Physical Review 140 (1965) A1133–A1138. doi:10.1103/physrev.140.a1133.
[26] J. Thijssen, Computational Physics, Cambridge University Press, 2007. doi:10.1017/ cbo9781139171397.
[27] E. Engel, R. M. Dreizler, Density Functional Theory: An Advanced Course, Springer Berlin Heidelberg, 2011. doi:10.1007/978-3-642-14090-7.
[28] J. P. Perdew, A. Zunger, Self-interaction correction to density-functional approximations for many-electron systems, Physical Review B 23 (1981) 5048–5079. doi:10.1103/physrevb.23.5048.
[29] S. H. Vosko, L. Wilk, M. Nusair, Accurate spin-dependent electron liquid correlation energies for local spin density calculations: a critical analysis, Canadian Journal of Physics 58 (1980) 1200– 1211. doi:10.1139/p80-159.
[30] J. P. Perdew, Y. Wang, Accurate and simple analytic representation of the electron-gas correlation energy, Physical Review B 45 (1992) 13244–13249. doi:10.1103/physrevb.45.13244.
[31] J. P. Perdew, K. Burke, M. Ernzerhof, Generalized gradient approximation made simple, Physical Review Letters 77 (1996) 3865–3868. doi:10.1103/physrevlett.77.3865.
[32] Y. Zhang, W. Yang, Commenton “generalized gradient approximation made simple”, Physical Review Letters 80 (1998) 890–890. doi:10.1103/physrevlett.80.890.
[33] B. Hammer, L. B. Hansen, J. K. Nørskov, Improved adsorption energetic swithin density-functional theory using revised perdew-burke-ernzerhof functionals, Physical Review B 59 (1999) 7413– 7421. doi:10.1103/physrevb.59.7413.
[34] D. R. Hamann, M. Schlüter, C. Chiang, Norm-conserving pseudopotentials, Phys. Rev. Lett. 43 (1979) 1494–1497. doi:10.1103/PhysRevLett.43.1494.
[35] A. M. Rappe, K. M. Rabe, E. Kaxiras, J. D. Joannopoulos, Optimized pseudopotentials, Phys. Rev. B 41 (1990) 1227–1230. doi:10.1103/PhysRevB.41.1227.
[36] N. Troullier, J. L. Martins, Efficient pseudopotentials for plane-wave calculations, Phys. Rev. B 43 (1991) 1993–2006. doi:10.1103/PhysRevB.43.1993.
[37] D. R. Hamann, Optimized norm-conserving vanderbilt pseudopotentials, Phys. Rev. B 88 (2013) 085117. doi:10.1103/PhysRevB.88.085117.
[38] C. Kittel, P. McEuen, J. W. . Sons, Introduction to Solid State Physics, John Wiley & Sons, 2005. URL: https://books.google.com.tw/books?id=rAMujwEACAAJ.
[39] N. Ashcroft, N. Mermin, Solid State Physics, Cengage Learning, 2011. URL: https://books. google.com.tw/books?id=x_s_YAAACAAJ.
[40] S. Datta, Electronic Transport in Mesoscopic Systems, Cambridge Studies in Semiconductor Physics and Microelectronic Engineering, Cambridge University Press, 1995. doi:10.1017/ CBO9780511805776.
[41] J. Taylor, H. Guo, J. Wang, Ab initio modeling of quantum transport properties of molecular electronic devices, Physical Review B 63 (2001) 245407. doi:10.1103/physrevb.63.245407.
[42] Y. Zhu, L. Liu, H. Guo, Atomistic Simulation of Quantum Transport in Nanoelectronic Devices: (With CD-ROM), WORLD SCIENTIFIC, 2016. doi:10.1142/10072.
[43] M. Soriano, J. J. Palacios, Theory of projections with nonorthogonal basis sets: Partitioning techniques and effective hamiltonians, Physical Review B 90 (2014) 075128. doi:10.1103/ PhysRevB.90.075128.
[44] M. Pourfath, The Non-Equilibrium Green’s Function Method for Nanoscale Device Simulation, Springer Vienna, 2014. URL: http://dx.doi.org/10.1007/978-3-7091-1800-9. doi:10. 1007/978-3-7091-1800-9.
[45] L. Keldysh, Ionization in the field of a strong electromagnetic wave, Journal of Experimental and Theoretical Physics 20 (1965) 1307–1314.
[46] A.-P. Jauho, N.S. Wingreen, Y. Meir, Time-dependent transport in interacting and noninteracting resonant-tunneling systems, Physical Review B 50 (1994) 5528–5544. doi:10.1103/PhysRevB. 50.5528.
[47] Y.-H. Tang, N. Kioussis, A. Kalitsov, W. H. Butler, R. Car, Influence of asymmetry on bias behavior of spin torque, Physical Review B 81 (2010) 054437. doi:10.1103/PhysRevB.81.054437.
[48] B.-H. Huang, Y.-H. Fu, C.-C. Kaun, Y.-H. Tang, Determining perpendicular magnetic anisotropy in Fe/MgO/Fe magnetic tunnel junction: A DFT-based spin–orbit torque method, Journal of Magnetism and Magnetic Materials 585 (2023) 171098. doi:10.1016/j.jmmm.2023.171098.
[49] S. Zhang, Z. Li, Roles of nonequilibrium conduction electrons on the magnetization dynamics of ferromagnets, Physical Review Letters 93 (2004) 127204. doi:10.1103/PhysRevLett.93. 127204.
[50] D. Ralph, M. Stiles, Spin transfer torques, Journal of Magnetism and Magnetic Materials 320 (2008) 1190–1216. doi:10.1016/j.jmmm.2007.12.019.
[51] A. Manchon, S. Zhang, Theory of spin torque due to spin-orbit coupling, Physical Review B 79 (2009) 094422. doi:10.1103/PhysRevB.79.094422.
[52] P. M. Haney, M. D. Stiles, Current-Induced Torques in the Presence of Spin-Orbit Coupling, Physical Review Letters 105 (2010) 126602. doi:10.1103/physrevlett.105.126602.
[53] P. M. Haney, D. Waldron, R. A. Duine, A. S. Núñez, H. Guo, A. H. MacDonald, Current-induced order parameter dynamics: Microscopic theory applied to Co/Cu/Co spin valves, Physical Review B 76 (2007) 024404. doi:10.1103/PhysRevB.76.024404.
[54] A. Kalitsov, I. Theodonis, N. Kioussis, M. Chshiev, W. H. Butler, A. Vedyayev, Spin-polarized current-induced torque in magnetic tunnel junctions, Journal of Applied Physics 99 (2006) 08G501. doi:10.1063/1.2151796.
[55] T. N. Todorov, Tight-binding simulation of current-carrying nanostructures, Journal of Physics: Condensed Matter 14 (2002) 3049–3084. doi:10.1088/0953-8984/14/11/314.
[56] D. Go, F. Freimuth, J.-P. Hanke, F. Xue, O. Gomonay, K.-J. Lee, S. Blügel, P. M. Haney, H.-W. Lee, Y. Mokrousov, Theory of current-induced angular momentum transfer dynamics in spin-orbit coupled systems, Physical Review Research 2 (2020) 033401. doi:10.1103/PhysRevResearch. 2.033401.
[57] L. Landau, E. Lifshitz, On the theory of the dispersion of magnetic permeability in ferromagnetic bodies, in: Perspectives in Theoretical Physics, Elsevier, 1992, pp. 51–65. doi:10.1016/ b978-0-08-036364-6.50008-9.
[58] T. Gilbert, Classics in magnetics a phenomenological theory of damping in ferromagnetic materials, IEEE Transactions on Magnetics 40 (2004) 3443–3449. doi:10.1109/tmag.2004. 836740.
[59] K. Dolui, M. D. Petrović, K. Zollner, P. Plecháč, J. Fabian, B. K. Nikolić, Proximity spin– orbit torque on a two-dimensional magnet within van der waals heterostructure: Current-driven antiferromagnet-to-ferromagnet reversible nonequilibrium phase transition in bilayer CrI3, Nano Letters 20 (2020) 2288–2295. doi:10.1021/acs.nanolett.9b04556.
[60] I. Theodonis, N. Kioussis, A. Kalitsov, M. Chshiev, W. H. Butler, Anomalous bias dependence of spin torque in magnetic tunnel junctions, Physical Review Letters 97 (2006) 237205. doi:10. 1103/PhysRevLett.97.237205.
[61] M. Brandbyge, J.-L. Mozos, P. Ordejón, J. Taylor, K. Stokbro, Density-functional method for nonequilibrium electron transport, Physical Review B 65 (2002) 165401. doi:10.1103/ PhysRevB.65.165401.
[62] Y.-H. Tang, B.-H. Huang, Underlying mechanism for exchange bias in single-molecule magnetic junctions, Physical Review Research 3 (2021) 033264. doi:10.1103/PhysRevResearch.3. 033264.
[63] C. Leighton, M. R. Fitzsimmons, P. Yashar, A. Hoffmann, J. Nogués, J. Dura, C. F. Majkrzak, I. K. Schuller, Two-stage magnetization reversal in exchange biased bilayers, Physical Review Letters 86 (2001) 4394–4397. doi:10.1103/PhysRevLett.86.4394.
[64] W.-G. Wang, M. Li, S. Hageman, C. L. Chien, Electric-field-assisted switching in magnetic tunnel junctions, Nature 11 (2012) 64–68. doi:10.1038/nmat3171.
[65] J. Nogués, I. K. Schuller, Exchange bias, Journal of Magnetism and Magnetic Materials 192 (1999) 203–232. doi:10.1016/s0304-8853(98)00266-2.
[66] B.-Y. Wang, C.-C. Chiu, W.-C. Lin, M.-T. Lin, Enhanced perpendicular magnetic anisotropy in Fe/Mn bilayers by incorporating ultrathin ferromagnetic underlayer through magnetic proximity effect, Applied Physics Letters 103 (2013). doi:10.1063/1.4816478.
[67] P. K. Srivastava, Y. Hassan, H. Ahn, B. Kang, S.-G. Jung, Y. Gebredingle, M. Joe, M. S. Abbas, T. Park, J.-G. Park, K.-J. Lee, C. Lee, Exchange bias effect in ferro-/antiferromagnetic van der waals heterostructures, Nano Letters 20 (2020) 3978–3985. doi:10.1021/acs.nanolett. 0c01176.
[68] Y. Fan, K. J. Smith, G. Lüpke, A. T. Hanbicki, R. Goswami, C. H. Li, H. B. Zhao, B. T. Jonker, Exchange bias of the interface spin system at the fe/mgo interface, Nature Nanotechnology 8 (2013) 438–444. doi:10.1038/nnano.2013.94.
[69] P.-H. Lin, B.-Y. Yang, M.-H. Tsai, P.-C. Chen, K.-F. Huang, H.-H. Lin, C.-H. Lai, Manipulating exchange bias by spin–orbit torque, Nature Materials 18 (2019) 335–341. doi:10.1038/ s41563-019-0289-4.
[70] P. M. Haney, C. Heiliger, M. D. Stiles, Bias dependence of magnetic exchange interactions: Application to interlayer exchange coupling in spin valves, Physical Review B 79 (2009) 054405. doi:10.1103/PhysRevB.79.054405.
[71] Y.-H. Tang, N. Kioussis, A. Kalitsov, W. H. Butler, R. Car, Controlling the nonequilibrium interlayer exchange coupling in asymmetric magnetic tunnel junctions, Physical Review Letters 103 (2009) 057206. doi:10.1103/PhysRevLett.103.057206.
[72] C. Ortiz Pauyac, A. Kalitsov, A. Manchon, M. Chshiev, Spin-transfer torque in spin filter tunnel junctions, Physical Review B 90 (2014) 235417. doi:10.1103/PhysRevB.90.235417.
[73] Y.-H. Tang, F.-C. Chu, N. Kioussis, Dual control of giant field-like spin torque in spin filter tunnel junctions, Scientific Reports 5 (2015) 11341. doi:10.1038/srep11341.
[74] Y.-H. Tang, Z.-W. Huang, B.-H. Huang, Analytic expression for the giant fieldlike spin torque in spin-filter magnetic tunnel junctions, Physical Review B 96 (2017) 064429. doi:10.1103/ PhysRevB.96.064429.
[75] J. M. De Teresa, A. Barthélémy, A. Fert, J. P. Contour, F. Montaigne, P. Seneor, Role of metal- oxide interface in determining the spin polarization of magnetic tunnel junctions, Science 286 (1999) 507–509. doi:10.1126/science.286.5439.507.
[76] Z. H. Xiong, D. Wu, Z. V. Vardeny, J. Shi, Giant magnetoresistance in organic spin-valves, Nature 427 (2004) 821–824. doi:10.1038/nature02325.
[77] J. C. Slonczewski, Currents, torques, and polarization factors in magnetic tunnel junctions, Physical Review B 71 (2005) 024411. doi:10.1103/PhysRevB.71.024411.
[78] S. Sanvito, The rise of spinterface science, Nature Physics 6 (2010) 562–564. doi:10.1038/ nphys1714.
[79] C.-H. Hsu, Y.-H. Chu, C.-I. Lu, P.-J. Hsu, S.-W. Chen, W.-J. Hsueh, C.-C. Kaun, M.-T. Lin, Spin- polarized transport through single manganese phthalocyanine molecules on a co nanoisland, The Journal of Physical Chemistry C 119 (2015) 3374–3378. doi:10.1021/jp510930y.
[80] M. Cinchetti, V. A. Dediu, L. E. Hueso, Activating the molecular spinterface, Nature Materials 16 (2017) 507–515. doi:10.1038/nmat4902.
[81] X. Zhang, J. Tong, L. Ruan, X. Yao, L. Zhou, F. Tian, G. Qin, Interface hybridization and spin filter effect in metal-free phthalocyanine spin valves, Physical Chemistry Chemical Physics 22 (2020) 11663–11670. doi:10.1039/D0CP00651C.
[82] R. Yamada, M. Noguchi, H. Tada, Magnetoresistance of single molecular junctions measured by a mechanically controllable break junction method, Applied Physics Letters 98 (2011) 053110. doi:10.1063/1.3549190.
[83] R. J. Brooke, C. Jin, D. S. Szumski, R. J. Nichols, B.-W. Mao, K. S. Thygesen, W. Schwarzacher, Single-molecule electrochemical transistor utilizing a nickel-pyridyl spinterface, Nano Letters 15 (2015) 275–280. doi:10.1021/nl503518q.
[84] S. Ding, Y. Tian, Y. Li, W. Mi, H. Dong, X. Zhang, W. Hu, D. Zhu, Inverse magnetoresistance in polymer spin valves, ACS Applied Materials & Interfaces 9 (2017) 15644–15651. doi:10.1021/ acsami.7b02804.
[85] A. C. Aragonès, E. Medina, M. Ferrer-Huerta, N. Gimeno, M. Teixidó, J. L. Palma, N. Tao, J. M. Ugalde, E. Giralt, I. Díez-Pérez, V. Mujica, Measuring the spin-polarization power of a single chiral molecule, Small 13 (2017) 1602519. doi:10.1002/smll.201602519.
[86] G. Ke, C. Duan, F. Huang, X. Guo, Electrical and spin switches in single-molecule junctions, InfoMat 2 (2020) 92–112. doi:10.1002/inf2.12068.
[87] D. Liu, Y. Hu, H. Guo, X. F. Han, Magnetic proximity effect at the molecular scale: First-principles calculations, Physical Review B 78 (2008) 193307. doi:10.1103/PhysRevB.78.193307.
[88] S. Mandal, R. Pati, What determines the sign reversal of magnetoresistance in a molecular tunnel junction?, ACS Nano 6 (2012) 3580–3588. doi:10.1021/nn3006569.
[89] D. Li, R. Banerjee, S. Mondal, I. Maliyov, M. Romanova, Y. J. Dappe, A. Smogunov, Symmetry aspects of spin filtering in molecular junctions: Hybridization and quantum interference effects, Physical Review B 99 (2019) 115403. doi:10.1103/PhysRevB.99.115403.
[90] S. Li, Y. Wang, Y. Wang, S. Sanvito, S. Hou, High-performance spin filters based on 1,2,4,5- tetrahydroxybenzene molecules attached to bulk nickel electrodes, The Journal of Physical Chemistry C 125 (2021) 6945–6953. doi:10.1021/acs.jpcc.1c00773.
[91] Y.-H. Tang, B.-H. Huang, Manipulation of giant field-like spin torque in amine-ended single- molecule magnetic junctions, The Journal of Physical Chemistry C 122 (2018) 20500–20505. doi:10.1021/acs.jpcc.8b03772.
[92] S. Haku, A. Ishikawa, A. Musha, H. Nakayama, T. Yamamoto, K. Ando, Surface rashba-edelstein spin-orbit torque revealed by molecular self-assembly, Physical Review Applied 13 (2020) 044069. doi:10.1103/PhysRevApplied.13.044069.
[93] M. Ratner, A brief history of molecular electronics, Nature Nanotechnology 8 (2013) 378–381. doi:10.1038/nnano.2013.110.
[94] T. A. Su, M. Neupane, M. L. Steigerwald, L. Venkataraman, C. Nuckolls, Chemical principles of single-molecule electronics, Nature Reviews Materials 1 (2016). doi:10.1038/natrevmats. 2016.2.
[95] P. Gehring, J. M. Thijssen, H. S. J. vander Zant, Single-molecule quantum-transport phenomenain break junctions, Nature Reviews Physics 1 (2019) 381–396. doi:10.1038/s42254-019-0055-1.
[96] B. Q. Xu, X. L. Li, X. Y. Xiao, H. Sakaguchi, N. J. Tao, Electromechanical and conductance switching properties of single oligothiophene molecules, Nano Letters 5 (2005) 1491–1495. doi:10.1021/nl050860j.
[97] B.-H. Huang, Y.-H. Tang, The detailed information of JUNPY package can be found at the website, 2016. URL: https://labstt.phy.ncu.edu.tw/junpy.
[98] P. Giannozzi, S. Baroni, N. Bonini, M. Calandra, R. Car, C. Cavazzoni, D. Ceresoli, G. L. Chiarotti, M. Cococcioni, I. Dabo, A. D. Corso, S. de Gironcoli, S. Fabris, G. Fratesi, R. Gebauer, U. Gerstmann, C. Gougoussis, A. Kokalj, M. Lazzeri, L. Martin-Samos, N. Marzari, F. Mauri, R. Mazzarello, S. Paolini, A. Pasquarello, L. Paulatto, C. Sbraccia, S. Scandolo, G. Sclauzero, A. P. Seitsonen, A. Smogunov, P. Umari, R. M. Wentzcovitch, QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials, Journal of Physics: Condensed Matter 21 (2009) 395502. doi:10.1088/0953-8984/21/39/395502.
[99] D. Waldron, L. Liu, H. Guo, Ab initio simulation of magnetic tunnel junctions, Nanotechnology 18 (2007) 424026. doi:10.1088/0957-4484/18/42/424026.
[100] Y. Ke, K. Xia, H. Guo, Disorder scattering in magnetic tunnel junctions: Theory of nonequilibrium vertex correction, Physical Review Letters 100 (2008) 166805. doi:10.1103/PhysRevLett.100. 166805.
[101] D. J. P. de Sousa, P. M. Haney, D. L. Zhang, J. P. Wang, T. Low, Bidirectional switching assisted by interlayer exchange coupling in asymmetric magnetic tunnel junctions, Physical Review B 101 (2020) 081404. doi:10.1103/PhysRevB.101.081404.
[102] J. Xiao, A. Zangwill, M. D. Stiles, Macrospin models of spin transfer dynamics, Physical Review B 72 (2005) 014446. doi:10.1103/physrevb.72.014446.
[103] Y. H. Tang, C. J. Lin, Strain-enhanced spin injection in amine-ended single-molecule magnetic junctions, The Journal of Physical Chemistry C 120 (2016) 692–696. doi:10.1021/acs.jpcc. 5b09700.
[104] J. R. Petta, S. K. Slater, D. C. Ralph, Spin-dependent transport in molecular tunnel junctions, Physical Review Letters 93 (2004) 136601. doi:10.1103/PhysRevLett.93.136601.
[105] L. Bogani, W. Wernsdorfer, Molecular spintronics using single-molecule magnets, Nature Materials 7 (2008) 179–186. doi:10.1038/nmat2133.
[106] K.-R. Chiang, Y.-H. Tang, Effect of contact geometry on spin transport in amine-ended single- molecule magnetic junctions, ACS Omega 6 (2021) 19386–19391. doi:10.1021/acsomega. 1c00930.
[107] S. Ikeda, K. Miura, H. Yamamoto, K. Mizunuma, H. D. Gan, M. Endo, S. Kanai, J. Hayakawa, F. Matsukura, H. Ohno, A perpendicular-anisotropy CoFeB–MgO magnetic tunnel junction, Nature Materials 9 (2010) 721–724. doi:10.1038/nmat2804.
[108] M. Weinert, R. E. Watson, J. W. Davenport, Total-energy differences and eigenvalue sums, Physical Review B 32 (1985) 2115–2119. doi:10.1103/PhysRevB.32.2115.
[109] G. H. O. Daalderop, P. J. Kelly, M. F. H. Schuurmans, First-principles calculation of the magnetocrystalline anisotropy energy of iron, cobalt, and nickel, Physical Review B 41 (1990) 11919–11937. doi:10.1103/PhysRevB.41.11919.
[110] S. Peng, M.Wang, H. Yang, L. Zeng, J. Nan, J. Zhou, Y. Zhang, A. Hallal, M. Chshiev, K. L. Wang, Q. Zhang, W. Zhao, Origin of interfacial perpendicular magnetic anisotropy in MgO/CoFe/metallic capping layer structures, Scientific Reports 5 (2015) 18173. doi:10.1038/srep18173.
[111] S. Peng, W. Zhao, J. Qiao, L. Su, J. Zhou, H. Yang, Q. Zhang, Y. Zhang, C. Grezes, P. K. Amiri, K. L. Wang, Giant interfacial perpendicular magnetic anisotropy in MgO/CoFe/capping layer structures, Applied Physics Letters 110 (2017) 072403. doi:10.1063/1.4976517.
[112] X. Wang, R. Wu, D. shengWang, A. J. Freeman, Torque method for the theoretical determination of magnetocrystalline anisotropy, Physical Review B 54 (1996) 61–64. doi:10.1103/physrevb. 54.61.
[113] Š. Pick, Magnetic anisotropy calculation: implementation of the torque method into the recursion-technique scheme, Solid State Communications 111 (1999) 15–18. doi:10.1016/S0038-1098(99)00170-2.
[114] A. Manchon, J. Železný, I. M. Miron, T. Jungwirth, J. Sinova, A. Thiaville, K. Garello, P. Gambardella, Current-induced spin-orbit torques in ferromagnetic and antiferromagnetic systems, Reviews of Modern Physics 91 (2019) 035004. doi:10.1103/RevModPhys.91.035004.
[115] G. Kresse, J. Furthmüller, Efficient iterative schemes for ab inition total-energy calculations using a plane-wave basis set, Physical Review B 54 (1996) 11169–11186. doi:10.1103/physrevb.54.11169.
[116] G. Kresse, D. Joubert, From ultrasoft pseudopotential sto the projector augmented-wavemethod, Physical Review B5 9 (1999) 1758–1775. doi:10.1103/physrevb.59.1758.
[117] P. Haney, R. Duine, A. Núñez, A. MacDonald, Current-induced torques in magnetic metals: Beyond spin-transfer, Journal of Magnetism and Magnetic Materials 320 (2008) 1300–1311. doi:10.1016/j.jmmm.2007.12.020.
[118] C. Heiliger, M. D. Stiles, Ab initio studies of the spin-transfer torque in magnetic tunnel junctions, Physical Review Letters 100 (2008) 186805. doi:10. 1103/PhysRevLett.100.186805.
[119] X. Jia, K. Xia, Y. Ke, H. Guo, Nonlinear bias dependence of spin-transfer torque from atomic first principles, Physical Review B 84 (2011) 014401. doi:10.1103/PhysRevB.84.014401.
[120] J. C. Sankey, Y.-T. Cui, J. Z. Sun, J. C. Slonczewski, R. A. Buhrman, D. C. Ralph, Measurement of the spin-transfer-torque vector in magnetic tunnel junctions, Nature Physics 4 (2008) 67–71. doi:10.1038/nphys783.
[121] M. D. Stiles, A. Zangwill, Anatomy of spin-transfer torque, Physical Review B 66 (2002) 014407. doi:10.1103/PhysRevB.66.014407.
[122] J. C. Slonczewski, Mechanism of interlayer exchange in magnetic multilayers, Journal of Magnetism and Magnetic Materials 126 (1993) 374–379. doi:10.1016/0304-8853(93)90630-k.
[123] P. Bruno, Theory of interlayer magnetic coupling, Physical Review B 52 (1995) 411–439. doi:10.1103/PhysRevB.52.411.
[124] H. X. Yang, M. Chshiev, B. Dieny, J. H. Lee, A. Manchon, K. H. Shin, First-principles investigation of the very large perpendicular magnetic anisotropy at Fe/MgO and Co/MgO interfaces, Physical Review B 84 (2011) 054401. doi:10.1103/physrevb.84.054401.
[125] B. Dieny, M. Chshiev, Perpendicular magnetic anisotropy at transition metal/oxide interfaces and applications, Reviews of Modern Physics 89 (2017) 025008. doi:10.1103/revmodphys.89.025008.
[126] B.-H. Huang, Y.-F. Lai, Y.-H. Tang, Validity of DFT-based spin-orbit torque calculation for perpendicular magnetic anisotropy in iron thin films, AIP Advances 13 (2023) 015034. doi:10.1063/9.0000481.
[127] S. Shi, Y. Ou, S. V. Aradhya, D. C. Ralph, R. A. Buhrman, Fast low-current spin-orbit-torque switching of magnetic tunnel junctions through atomic modifications of the free-layer interfaces, Physical Review Applied 9 (2018) 011002. doi:10.1103/PhysRevApplied.9.011002.
[128] L. Liu, C.-F. Pai, Y. Li, H. W. Tseng, D. C. Ralph, R. A. Buhrman, Spin-torque switching with the giant spin hall effect of tantalum, Science 336 (2012) 555–558. doi:10.1126/science.1218197.
[129] L. Zhu, D. C. Ralph, R. A. Buhrman, Spin-orbit torques in heavy-metal–ferromagnet bilayers with varying strengths of interfacial spin-orbit coupling, Physical Review Letters 122 (2019) 077201. doi:10.1103/PhysRevLett.122.077201.
[130] L. Liu, O. J. Lee, T. J. Gudmundsen, D. C. Ralph, R. A. Buhrman, Current-Induced Switching of Perpendicularly Magnetized Magnetic Layers Using Spin Torque from the Spin Hall Effect, Physical Review Letters 109 (2012) 096602. doi:10.1103/physrevlett.109.096602.
[131] K. Garello, I. M. Miron, C. O. Avci, F. Freimuth, Y. Mokrousov, S. Blügel, S. Auffret, O. Boulle, G. Gaudin, P. Gambardella, Symmetry and magnitude of spin–orbit torques in ferromagnetic heterostructures, Nature Nanotechnology 8 (2013) 587–593. doi:10.1038/nnano.2013.145.
[132] V. Edelstein, Spin polarization of conduction electrons induced by electric current in two-dimensional asymmetric electron systems, Solid State Communications 73 (1990) 233–235. doi:10.1016/0038-1098(90)90963-c.
[133] I. M. Miron, K. Garello, G. Gaudin, P.-J. Zermatten, M. V. Costache, S. Auffret, S. Bandiera, B. Rodmacq, A. Schuhl, P. Gambardella, Perpendicular switching of a single ferromagnetic layer induced by in-plane current injection, Nature 476 (2011) 189–193. doi:10.1038/nature10309.
[134] I. Shin, W. J. Cho, E. An, S. Park, H. Jeong, S. Jang, W. J. Baek, S. Y. Park, D. Yang, J. H. Seo, G. Kim, M. N. Ali, S. Choi, H. Lee, J. S. Kim, S. D. Kim,
[135] G. Lee, Spin–orbit torque switching in an all‐van der waals heterostructure, Advanced Materials 34 (2022) 2101730. doi:10.1002/adma.202101730. P. M. Haney, H.-W. Lee, K.-J. Lee, A. Manchon, M. D. Stiles, Current-induced torques and interfacial spin-orbit coupling, Physical Review B 88 (2013) 214417. doi:10.1103/physrevb.88.214417.
[136] F. Mahfouzi, R. Mishra, P.-H. Chang, H. Yang, N. Kioussis, Microscopic origin of spin-orbit torque in ferromagnetic heterostructures: A first-principles approach, Physical Review B 101 (2020) 060405. doi:10.1103/physrevb.101.060405.
[137] K.-W. Kim, K.-J. Lee, J. Sinova, H.-W. Lee, M. D. Stiles, Spin-orbit torques from interfacial spin-orbit coupling for various interfaces, Physical Review B 96 (2017) 104438. doi:10.1103/physrevb.96.104438.
[138] H. Xu, J. Wei, H. Zhou, J. Feng, T. Xu, H. Du, C. He, Y. Huang, J. Zhang, Y. Liu, H. Wu, C. Guo, X. Wang, Y. Guang, H. Wei, Y. Peng, W. Jiang, G. Yu,
[139] X. Han, High spin hall conductivity in large‐area type‐ii dirac semimetal PtTe2, Advanced Materials 32 (2020) 2000513. doi:10.1002/adma.202000513. W. Lv, Z. Jia, B. Wang, Y. Lu, X. Luo, B. Zhang, Z. Zeng, Z. Liu, Electric-field control of spin–orbit torques in WS2/permalloy bilayers, ACS Applied Materials Interfaces 10 (2018) 2843–2849. doi:10.1021/acsami.7b16919.
[140] S. Fukami, T. Anekawa, C. Zhang, H. Ohno, A spin–orbit torque switching scheme with collinear magnetic easy axis and current configuration, Nature Nanotechnology 11 (2016) 621–625. doi:10.1038/nnano.2016.29.
[141] S. Sharma, J. K. Dewhurst, C. Ambrosch-Draxl, S. Kurth, N. Helbig, S. Pittalis, S. Shallcross, L. Nordström, E. K. U. Gross, First-principles approach to noncollinear magnetism: Towards spin dynamics, Physical Review Letters 98 (2007) 196405. doi:10.1103/PhysRevLett.98.196405.
[142] F. G. Eich, E. K. U. Gross, Transverse spin-gradient functional for noncollinear spin-density-functional theory, Physical Review Letters 111 (2013) 156401. doi:10.1103/PhysRevLett.111.156401.
[143] T. P. Pareek, P. Bruno, Spin coherence in a two-dimensional electron gas with rashba spin-orbit interaction, Physical Review B 65 (2002) 241305. doi:10.1103/PhysRevB.65.241305.
[144] I. Theodonis, A. Kalitsov, N. Kioussis, Enhancingspin-transfer torque through the proximity of quantum well states, Physical Review B 76 (2007) 224406. doi:10.1103/PhysRevB.76.224406.
[145] A. Kalitsov, S. A. Nikolaev, J. Velev, M. Chshiev, O. Mryasov, Intrinsic spin-orbit torque in a single-domain nanomagnet, Physical Review B 96 (2017) 214430. doi:10.1103/PhysRevB.96.214430.
[146] L. Fernández-Seivane, M. A. Oliveira, S. Sanvito, J. Ferrer, On-site approximation for spin–orbit coupling in linear combination of atomic orbitals density functional methods, Journal of Physics: Condensed Matter 18 (2006) 7999–8013. doi:10.1088/0953-8984/18/34/012.

指導教授

唐毓慧(Yu-Hui Tang)

審核日期

2024-8-20

推文