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| DC 欄位 | 值 | 語言 |
|---|---|---|
| dc.contributor.advisor | 張慶瑞 | |
| dc.contributor.author | Yi-Chen Yang | en |
| dc.contributor.author | 楊毅楨 | zh_TW |
| dc.date.accessioned | 2021-06-13T03:21:11Z | - |
| dc.date.available | 2006-07-31 | |
| dc.date.copyright | 2006-07-31 | |
| dc.date.issued | 2006 | |
| dc.date.submitted | 2006-07-28 | |
| dc.identifier.citation | [1] J. Slonczewski, J. Magn. Magn. Mater. 159, L1 (1996).
[2] L. Berger, Phys. Rev. B 54, 9359 (1996). [3] Z. Li and S. Zhang, Phys. Rev. B 68, 024404 (2003) [4] Z. Li and S. Zhang, Phys. Rev. B 70, 024417 (2004) [5] S. Zhang and Z. Li, Phys. Rev. Lett. 93, 127204 (2004) [6] Z. Li, J. He and S. Zhang, J. Appl. Phys. 99, 08Q702 (2006) [7] F. Bloch 1932 ZS. f. Phys. 74 295. [8] L. Landau and E. Lifshitz, Phys. Z. Sowjetunion 8, 153 (1935). [9] S.Chikazumi, Physics of ferromagnetism,.Oxford University Press (1997). [10] T. L. Gilbert 1955 Proceeding of the Conference on Magnetism and Magnetic Materials, Pittsburg. [11] W. Doring 1948 Z. Maturforsch (German) 3a 373-379. [12] S.I. Kiselev, J.C. Sankey, I.N. Krivorotov, N.C. Emley, R.J. Schoelkopf, R.A. Buhrman, D. C. Ralph, Letters to Nature 425, p. 380 (2003). [13] S. Urazhdin, N. O. Birge, W. P.Pratt, J. Bass, Phys. Rev. Lett. 91, 146803 (2003) [14] A. Yamaguchi, T. Ono, S. Nasu, Phys. Rev. Lett. 92, 077205 (2004) [15] M. Klaui et al., Phys. Rev. Lett. 95, 026601 (2005) [16] N. L. Schryer and L. R. Walker, J. Appl. Phys. 45, 5406 (1974). [17] Gerald, Applied numerical analysis, Wheatley sixth edition. | |
| dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/31820 | - |
| dc.description.abstract | Abstract
When a spin-polarized current ‡ows through a ferromagnet, the local magnetization receives a spin transfer torque. In one-dimention approxi- mations, we solve the Landau-Lifshitz-Gilbert equation along with two spin torque terms, both analytically and numerically, to realize the behavior of a domain wall under the in‡uence of the spin-polarized current. As a …rst step, we focus on the system of domain wall within a perfect magnetic nanowire. Secondly, we consider the pinning case which may be caused by doping a high-Ku material into the system. By numerically solving the LLG equation, we …nd some characteristics of domain-wall motion under the spin-polarized current. In the presence of domain-wall pinning centers, we also de…ned the depinning …eld and construct a phase diagram for the domain-wall. | en |
| dc.description.provenance | Made available in DSpace on 2021-06-13T03:21:11Z (GMT). No. of bitstreams: 1 ntu-95-R92222046-1.pdf: 524616 bytes, checksum: d6e9de970fe459e36df65c56c39ef431 (MD5) Previous issue date: 2006 | en |
| dc.description.tableofcontents | Contents
1 Introduction 11 2 Theoretical background of micromagnetics 15 2.1 Domain wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.2 Micromagnetics . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.3 Landau-Lifshitz-Gilbert Equation . . . . . . . . . . . . . . . . 18 2.3.1 Gyrotropic Equation of Motion . . . . . . . . . . . . . 19 2.3.2 Damping term . . . . . . . . . . . . . . . . . . . . . . . 20 2.3.3 Main energy terms . . . . . . . . . . . . . . . . . . . . 20 2.3.4 One-dimensional Bloch wall theory . . . . . . . . . . . 25 3 Theoretical background of spin-transfer model 29 3.1 Spin transfer e¤ect . . . . . . . . . . . . . . . . . . . . . . . . 29 3.2 Landau-Lifshitz-Gilbert equation with spin torque terms . . . 31 4 Analytic solution of current-driven domain wall motion 35 4.1 Model of the system . . . . . . . . . . . . . . . . . . . . . . . 35 4.2 Model calculations . . . . . . . . . . . . . . . . . . . . . . . . 37 4.3 Results and discussions . . . . . . . . . . . . . . . . . . . . . . 40 4.4 The special case: simple pendulum . . . . . . . . . . . . . . . 41 5 Numerical study of current-driven domain wall motion 45 5.1 Computational method of micromagnetics . . . . . . . . . . . 45 5.2 Discussion about units and typical values of parameters . . . . 47 5.3 Numerical results of domain wall motion in a perfect nanowire 48 5.3.1 Under the in‡uence of external magnetic …eld . . . . . 48 5.3.2 Under the in‡uence of adiabatic spin torque . . . . . . 50 5.3.3 Under the in‡uence of non-adiabatic spin torque . . . . 53 5.4 Numerical results of domain wall motion in a nanowire with a pinning center . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 5.4.1 Under the in‡uence of external magnetic …eld . . . . . 55 5.4.2 Under the in‡uence of spin current . . . . . . . . . . . 59 6 Summary 61 Bibliography 62 | |
| dc.language.iso | en | |
| dc.subject | 磁壁 | zh_TW |
| dc.subject | Spin-Polarized Current | en |
| dc.subject | Domain Wall Motion | en |
| dc.title | 磁壁在磁場及極化自旋電流下之運動行為 | zh_TW |
| dc.title | One-Dimentional Wall Motion Driven by Magnetic Field and Spin-Polarized Current | en |
| dc.type | Thesis | |
| dc.date.schoolyear | 94-2 | |
| dc.description.degree | 碩士 | |
| dc.contributor.oralexamcommittee | 楊志信,賴梅鳳 | |
| dc.subject.keyword | 磁壁, | zh_TW |
| dc.subject.keyword | Domain Wall Motion,Spin-Polarized Current, | en |
| dc.relation.page | 64 | |
| dc.rights.note | 有償授權 | |
| dc.date.accepted | 2006-07-30 | |
| dc.contributor.author-college | 理學院 | zh_TW |
| dc.contributor.author-dept | 物理研究所 | zh_TW |
| 顯示於系所單位： | 物理學系 | |
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