請用此 Handle URI 來引用此文件：
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/81179完整後設資料紀錄
| DC 欄位 | 值 | 語言 |
|---|---|---|
| dc.contributor.advisor | 白奇峰(Chi-Feng Pai) | |
| dc.contributor.author | Ting-Yu Chang | en |
| dc.contributor.author | 張庭瑀 | zh_TW |
| dc.date.accessioned | 2022-11-24T03:34:38Z | - |
| dc.date.available | 2021-08-10 | |
| dc.date.available | 2022-11-24T03:34:38Z | - |
| dc.date.copyright | 2021-08-10 | |
| dc.date.issued | 2021 | |
| dc.date.submitted | 2021-08-05 | |
| dc.identifier.citation | [1] R. Ramaswamy, J. M. Lee, K. Cai, and H. Yang, Recent advances in spin-orbit torques: Moving towards device applications, Appl. Phys. Rev. 5, 031107 (2018). [2] J. E. Hirsch, Spin Hall Effect, Phys. Rev. Lett. 83, 1834 (1999). [3] A. Hoffmann, Spin Hall Effects in Metals, IEEE Trans. Magn. 49, 5172 (2013). [4] C.-F. Pai, L. Liu, Y. Li, H. W. Tseng, D. C. Ralph, and R. A. Buhrman, Spin transfer torque devices utilizing the giant spin Hall effect of tungsten, Appl. Phys. Lett. 101, 122404 (2012). [5] L. Liu, C.-F. Pai, Y. Li, H. W. Tseng, D. C. Ralph, and R. A. Buhrman, Spin-Torque Switching with the Giant Spin Hall Effect of Tantalum, Science 336, 555 (2012). [6] A. R. Mellnik et al., Spin-transfer torque generated by a topological insulator, Nature 511, 449 (2014). [7] N. Nagaosa, J. Sinova, S. Onoda, A. H. MacDonald, and N. P. Ong, Anomalous Hall effect, Rev. Mod. Phys. 82, 1539 (2010). [8] V. M. Edelstein, Spin polarization of conduction electrons induced by electric current in two-dimensional asymmetric electron systems, Solid State Commun. 73, 233 (1990). [9] J. Schliemann and D. Loss, Anisotropic transport in a two-dimensional electron gas in the presence of spin-orbit coupling, Phys. Rev. B 68, 165311 (2003). [10] I. M. Miron et al., Fast current-induced domain-wall motion controlled by the Rashba effect, Nat. Mater. 10, 419 (2011). [11] W. Thomson, On the electro-dynamic qualities of metals:-Effects of magnetization on the electric conductivity of nickel and of iron, Proceedings of the Royal Society of London 8, 546 (1857). [12] W. Gil, D. Görlitz, M. Horisberger, and J. Kötzler, Magnetoresistance anisotropy of polycrystalline cobalt films: Geometrical-size and domain effects, Phys. Rev. B 72, 134401 (2005). [13] H. Nakayama et al., Spin Hall Magnetoresistance Induced by a Nonequilibrium Proximity Effect, Phys. Rev. Lett. 110, 206601 (2013). [14] M. I. Dyakonov and V. I. Perel, Current-induced spin orientation of electrons in semiconductors, Phys. Lett. A 35, 459 (1971). [15] S. Zhang, Spin Hall Effect in the Presence of Spin Diffusion, Phys. Rev. Lett. 85, 393 (2000). [16] C. O. Avci, K. Garello, A. Ghosh, M. Gabureac, S. F. Alvarado, and P. Gambardella, Unidirectional spin Hall magnetoresistance in ferromagnet/normal metal bilayers, Nat. Phys. 11, 570 (2015). [17] C. O. Avci, J. Mendil, G. S. Beach, and P. Gambardella, Origins of the unidirectional spin Hall magnetoresistance in metallic bilayers, Phys. Rev. Lett. 121, 087207 (2018). [18] C. O. Avci, K. Garello, J. Mendil, A. Ghosh, N. Blasakis, M. Gabureac, M. Trassin, M. Fiebig, and P. Gambardella, Magnetoresistance of heavy and light metal/ferromagnet bilayers, Appl. Phys. Lett. 107, 192405 (2015). [19] K. Yasuda, A. Tsukazaki, R. Yoshimi, K. S. Takahashi, M. Kawasaki, and Y. Tokura, Large Unidirectional Magnetoresistance in a Magnetic Topological Insulator, Phys Rev Lett 117, 127202 (2016). [20] Y. Lv, J. Kally, D. Zhang, J. S. Lee, M. Jamali, N. Samarth, and J.-P. Wang, Unidirectional spin-Hall and Rashba−Edelstein magnetoresistance in topological insulator-ferromagnet layer heterostructures, Nat. Commun. 9, 111 (2018). [21] N. H. Duy Khang and P. N. Hai, Giant unidirectional spin Hall magnetoresistance in topological insulator – ferromagnetic semiconductor heterostructures, J. Appl. Phys. 126, 233903 (2019). [22] Y.-T. Liu, T.-Y. Chen, T.-H. Lo, T.-Y. Tsai, S.-Y. Yang, Y.-J. Chang, J.-H. Wei, and C.-F. Pai, Determination of Spin-Orbit-Torque Efficiencies in Heterostructures with In-Plane Magnetic Anisotropy, Phys. Rev. Appl 13, 044032 (2020). [23] B. Raquet, M. Viret, E. Sondergard, O. Cespedes, and R. Mamy, Electron-magnon scattering and magnetic resistivity in 3d ferromagnets, Phys. Rev. B 66, 024433 (2002). [24] V. E. Demidov, S. Urazhdin, E. R. J. Edwards, M. D. Stiles, R. D. McMichael, and S. O. Demokritov, Control of Magnetic Fluctuations by Spin Current, Phys. Rev. Lett. 107, 107204 (2011). [25] A. P. Mihai, J. P. Attané, A. Marty, P. Warin, and Y. Samson, Electron-magnon diffusion and magnetization reversal detection in FePt thin films, Phys. Rev. B 77, 060401 (2008). [26] S. Langenfeld, V. Tshitoyan, Z. Fang, A. Wells, T. A. Moore, and A. J. Ferguson, Exchange magnon induced resistance asymmetry in permalloy spin-Hall oscillators, Appl. Phys. Lett. 108, 192402 (2016). [27] T. L. Gilbert, A phenomenological theory of damping in ferromagnetic materials, IEEE Trans. Magn. 40, 3443 (2004). [28] C. Kittel, Theory of the Dispersion of Magnetic Permeability in Ferromagnetic Materials at Microwave Frequencies, Physical Review 70, 281 (1946). [29] D. D. Tang and C.-F. Pai, MAGNETIC MEMORY TECHNOLOGY: Spin-transfer-torque Mram and Beyond. John Wiley and Sons. (2020). [30] J. C. Slonczewski, Current-driven excitation of magnetic multilayers, J. Magn. Magn. Mater. 159, L1 (1996). [31] L. Berger, Emission of spin waves by a magnetic multilayer traversed by a current, Phys. Rev. B 54, 9353 (1996). [32] B. K. Nikolić, K. Dolui, M. D. Petrović, P. Plecháč, T. Markussen, and K. Stokbro, First-principles quantum transport modeling of spin-transfer and spin-orbit torques in magnetic multilayers, Handbook of Materials Modeling: Applications: Current and Emerging Materials, 499 (2020). [33] D. Fang et al., Spin–orbit-driven ferromagnetic resonance, Nat. Nanotechnol. 6, 413 (2011). [34] J. Kim, J. Sinha, M. Hayashi, M. Yamanouchi, S. Fukami, T. Suzuki, S. Mitani, and H. Ohno, Layer thickness dependence of the current-induced effective field vector in Ta|CoFeB|MgO, Nat. Mater. 12, 240 (2013). [35] X. Qiu, P. Deorani, K. Narayanapillai, K.-S. Lee, K.-J. Lee, H.-W. Lee, and H. Yang, Angular and temperature dependence of current induced spin-orbit effective fields in Ta/CoFeB/MgO nanowires, Sci. Rep. 4, 4491 (2014). [36] M. Hayashi, J. Kim, M. Yamanouchi, and H. Ohno, Quantitative characterization of the spin-orbit torque using harmonic Hall voltage measurements, Phys. Rev. B 89, 144425 (2014). [37] Y. B. Bazaliy, B. A. Jones, and S.-C. Zhang, Current-induced magnetization switching in small domains of different anisotropies, Phys. Rev. B 69, 094421 (2004). [38] T. Xing et al., Direct detection of spin-orbit effective fields through magneto-optical Kerr effect, Phys. Rev. B 101, 224407 (2020). [39] G. Binasch, P. Grünberg, F. Saurenbach, and W. Zinn, Enhanced magnetoresistance in layered magnetic structures with antiferromagnetic interlayer exchange, Phys. Rev. B 39, 4828 (1989). [40] R. E. Camley and J. Barnaś, Theory of giant magnetoresistance effects in magnetic layered structures with antiferromagnetic coupling, Phys. Rev. Lett. 63, 664 (1989). [41] J. Hayakawa, S. Ikeda, Y. M. Lee, F. Matsukura, and H. Ohno, Effect of high annealing temperature on giant tunnel magnetoresistance ratio of CoFeB∕MgO∕CoFeB magnetic tunnel junctions, Appl. Phys. Lett. 89, 232510 (2006). [42] D. D. Djayaprawira, K. Tsunekawa, M. Nagai, H. Maehara, S. Yamagata, N. Watanabe, S. Yuasa, Y. Suzuki, and K. Ando, 230% room-temperature magnetoresistance in CoFeB∕MgO∕CoFeB magnetic tunnel junctions, Appl. Phys. Lett. 86, 092502 (2005). [43] S. Ikeda, J. Hayakawa, Y. Ashizawa, Y. M. Lee, K. Miura, H. Hasegawa, M. Tsunoda, F. Matsukura, and H. Ohno, Tunnel magnetoresistance of 604% at 300K by suppression of Ta diffusion in CoFeB∕MgO∕CoFeB pseudo-spin-valves annealed at high temperature, Appl. Phys. Lett. 93, 082508 (2008). [44] Y. Yin, D.-S. Han, M. C. de Jong, R. Lavrijsen, R. A. Duine, H. J. Swagten, and B. Koopmans, Thickness dependence of unidirectional spin-hall magnetoresistance in metallic bilayers, Appl. Phys. Lett. 111, 232405 (2017). [45] D. K. Maurya, A. Sardarinejad, and K. Alameh, Recent Developments in R.F. Magnetron Sputtered Thin Films for pH Sensing Applications—An Overview, Coatings 4, 756 (2014). [46] Q. Wang, S. Kishimoto, Y. Tanaka, and K. Naito, Fabrication of nanoscale speckle using broad ion beam milling on polymers for deformation analysis, Theor. Appl. Mech. Lett. 6, 157 (2016). [47] A. V. Khvalkovskiy, V. Cros, D. Apalkov, V. Nikitin, M. Krounbi, K. A. Zvezdin, A. Anane, J. Grollier, and A. Fert, Matching domain-wall configuration and spin-orbit torques for efficient domain-wall motion, Phys. Rev. B 87, 020402 (2013). [48] C.-F. Pai, Y. Ou, L. H. Vilela-Leão, D. C. Ralph, and R. A. Buhrman, Dependence of the efficiency of spin Hall torque on the transparency of Pt/ferromagnetic layer interfaces, Phys. Rev. B 92, 064426 (2015). [49] R. H. Koch, J. A. Katine, and J. Z. Sun, Time-Resolved Reversal of Spin-Transfer Switching in a Nanomagnet, Phys. Rev. Lett. 92, 088302 (2004). [50] A. V. Khvalkovskiy et al., Basic principles of STT-MRAM cell operation in memory arrays, J. Phys. D: Appl. Phys. 46, 139601 (2013). [51] J. Z. Sun, Spin-current interaction with a monodomain magnetic body: A model study, Phys. Rev. B 62, 570 (2000). [52] J. Liu, T. Ohkubo, S. Mitani, K. Hono, and M. Hayashi, Correlation between the spin Hall angle and the structural phases of early 5d transition metals, Appl. Phys. Lett. 107, 232408 (2015). [53] S. Mondal, S. Choudhury, N. Jha, A. Ganguly, J. Sinha, and A. Barman, All-optical detection of the spin Hall angle in W/CoFeB/SiO2 heterostructures with varying thickness of the tungsten layer, Phys. Rev. B 96, 054414 (2017). [54] T.-C. Wang, T.-Y. Chen, C.-T. Wu, H.-W. Yen, and C.-F. Pai, Comparative study on spin-orbit torque efficiencies from W/ferromagnetic and W/ferrimagnetic heterostructures, Phys. Rev. Mater. 2, 014403 (2018). [55] L. Zhu, D. C. Ralph, and R. A. Buhrman, Lack of Simple Correlation between Switching Current Density and Spin-Orbit-Torque Efficiency of Perpendicularly Magnetized Spin-Current-Generator--Ferromagnet Heterostructures, Phys. Rev. Appl 15, 024059 (2021). | |
| dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/81179 | - |
| dc.description.abstract | "磁阻效應 (Magnetoresistance) 描述在不同磁化量方向其縱向電阻的變化。至今為止，磁阻效應被廣泛研究並應用在硬碟 (hard-disk drive) 以及次世代磁阻式隨機存取記憶體 (next-generation magnetoresistive random access memory, MRAM) 上，例如巨磁阻 (GMR) 以及穿隧磁阻效應 (TMR)。近年來，人們發現自旋霍爾效應也能產生磁阻。這些磁阻不僅能用來表徵電荷流—自旋流轉化效率，同時也能用來作為磁性元件的讀取機制。這些磁阻分別為自旋霍爾磁阻 (SMR) 和單向磁阻 (UMR)。自旋霍爾磁阻描述透過吸收或反射自旋霍爾效應感應出的自旋流來造成層膜異質結構的電阻變化，而單向磁阻則是描述來自於自旋相關散射和磁振子-電子散射所造成的電阻變化。雖然單向磁阻可由上述兩種效應解釋，但其理論仍有缺陷。在這篇論文中，我通過施加大範圍的電流與外加磁場進行電流依賴及磁場依賴之單向磁阻量測，發現在鎢鈷鐵硼雙層異質結構中具有很大的單向磁阻值，其值大於過去研究中在室溫的金屬磁性異質結構中所量測到的單向磁阻。我也發現在大電流區間下有額外的機制出現並影響單向磁阻，而此機制與自旋霍爾磁阻一樣，與金屬磁性異質結構的阻尼似自旋矩轉移轉換效率 ( ) 有關。接著我進一步利用宏自旋模擬(macrospin simulation)驗證自旋霍爾感應的自旋矩與單向磁阻的關聯性，其說明了額外的單向磁阻是來自於磁化量的偏移。因此對於此額外的單向磁阻，我暫時將其稱之為自旋矩轉移單向磁阻(STT-UMR)。除此之外，藉由模擬及實驗結果，我可以估算阻尼似自旋矩轉移轉換效率。除此之外，我也進行電致磁化翻轉量測，發現阻尼似自旋矩轉移轉換效率的趨勢與藉由模擬和實驗數據估算出來的值相差不大。因此，我的研究成果說明了單向磁阻與自旋矩轉移之間強烈的關聯性，其對於探討單向電阻的來源以及應用可行性是有幫助的。" | zh_TW |
| dc.description.provenance | Made available in DSpace on 2022-11-24T03:34:38Z (GMT). No. of bitstreams: 1 U0001-0308202118144500.pdf: 3999490 bytes, checksum: af974179d6b6159dcd2f2ea5d4c401fb (MD5) Previous issue date: 2021 | en |
| dc.description.tableofcontents | 口試委員會審定書 ii 誌謝 iii 中文摘要 iv ABSTRACT v CONTENTS vii LIST OF FIGURES ix LIST OF TABLES xiii Chapter 1 Introduction 1 1.1 Spin-Orbit Interactions in Magnetic Heterostructures 1 1.1.1 Spin Hall Effect (SHE) 1 1.1.2 Rashba-Edelstein Effect 3 1.2 Magnetoresistance 4 1.2.1 Anisotropic Magnetoresistance (AMR) 4 1.2.2 Spin Hall Magnetoresistance (SMR) 5 1.2.3 Unidirectional Magnetoresistance (UMR) 7 1.3 Magnetization Dynamics 11 1.3.1 Landau-Lifshitz-Gilbert Equation (LLG equation) 11 1.3.2 Spin-Transfer Torque (STT) 12 1.3.3 Spin-Orbit Torque (SOT) 15 1.4 Motivation of This Work 17 Chapter 2 Experiments 19 2.1 Deposition 19 2.1.1 Magnetron Sputtering 19 2.2 Device Fabrication 21 2.2.1 Photo-Lithography 21 2.2.2 Ion Beam Etching 22 2.3 Measurement Methods 23 2.3.1 Anisotropic Magnetoresistance loop-shift Measurement 23 2.3.2 Unidirectional Magnetoresistance Measurement 26 2.3.3 Current-induced SOT-driven magnetization switching measurement 28 2.3.4 Pulse-Width Dependent Measurement 31 Chapter 3 Results 33 3.1 Field-scan Unidirectional Magnetoresistance 33 3.1.1 The Properties of Unidirectional Magnetoresistance 33 3.1.2 Field-Dependent Unidirectional Magnetoresistance 41 3.1.3 Current-Dependent Unidirectional Magnetoresistance 43 3.2 The analysis of slope Jinflection/Hy 47 3.2.1 The slope Jinflection/Hy results 47 3.2.2 Brief discussion 50 3.3 Spin-orbit-torque efficiencies 54 3.3.1 Damping-like Spin-orbit-torque efficiency 54 3.3.2 Field-like Spin-orbit-torque efficiency 57 Chapter 4 Conclusion 60 REFERENCE 62 | |
| dc.language.iso | en | |
| dc.subject | 微米尺寸元件 | zh_TW |
| dc.subject | 自旋霍爾效應 | zh_TW |
| dc.subject | 自旋矩轉移 | zh_TW |
| dc.subject | 磁性異質結構 | zh_TW |
| dc.subject | 磁阻 | zh_TW |
| dc.subject | magnetoresistance | en |
| dc.subject | micro-sized device | en |
| dc.subject | spin-torque transfer | en |
| dc.subject | spin Hall effect | en |
| dc.subject | magnetic heterostructure | en |
| dc.title | 磁性異質結構中自旋矩引發單向磁阻之研究 | zh_TW |
| dc.title | Study of Spin-Torque Induced Unidirectional Magnetoresistance in Magnetic Heterostructures | en |
| dc.date.schoolyear | 109-2 | |
| dc.description.degree | 碩士 | |
| dc.contributor.oralexamcommittee | 林昭吟(Hsin-Tsai Liu),洪振湧(Chih-Yang Tseng) | |
| dc.subject.keyword | 自旋霍爾效應,自旋矩轉移,磁性異質結構,磁阻,微米尺寸元件, | zh_TW |
| dc.subject.keyword | spin Hall effect,spin-torque transfer,magnetic heterostructure,magnetoresistance,micro-sized device, | en |
| dc.relation.page | 66 | |
| dc.identifier.doi | 10.6342/NTU202102056 | |
| dc.rights.note | 同意授權(限校園內公開) | |
| dc.date.accepted | 2021-08-06 | |
| dc.contributor.author-college | 工學院 | zh_TW |
| dc.contributor.author-dept | 材料科學與工程學研究所 | zh_TW |
| 顯示於系所單位： | 材料科學與工程學系 | |
文件中的檔案：
| 檔案 | 大小 | 格式 | |
|---|---|---|---|
| U0001-0308202118144500.pdf 授權僅限NTU校內IP使用（校園外請利用VPN校外連線服務） | 3.91 MB | Adobe PDF |
系統中的文件，除了特別指名其著作權條款之外，均受到著作權保護，並且保留所有的權利。