倾斜各向异性磁性多层膜中铁磁共振的理论研究
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摘要
近年来,自旋电子学由于其丰富的物理内涵和广泛的器件应用前景己成为凝聚态物理研究的热点领域。GMR和TMR等效应提出以来,便在读写磁头、磁存储元件、磁场探测器,微波激发等领域得到了广泛应用。特别是1996年“自旋转移矩”效应的理论预言和后面的实验证实,打破了传统的采用磁场来改变或翻转薄膜材料磁矩方向的方法,开创性地采用自旋极化电流直接实现磁矩反转或激发自旋波。本论文主要对倾斜各向异性磁性多层膜中的铁磁共振进行了理论研究。
首先,我们简单地介绍了铁磁材料中的相互作用能以及朗道-栗弗席兹-吉尔伯特(LLG)动力学方程。然后我们在只考虑各向异性能和退磁能的情形下,利用线性展开包含自旋转移矩的LLG动力学方程的方法,获得了电流和频率调节的铁磁共振谱,并且分析了平衡位置,共振位置和共振线宽随直流电流密度和钉扎层磁矩方向的变化关系,讨论了电流密度以及钉扎层磁矩方向对功率密度的影响。研究表明：通过选择合适的电流密度和钉扎层磁矩方向,可以从电流泵浦最大的能量到自由层。这一点对提高电流驱动的微波振荡器以及电流感应磁矩翻转的效率是非常有用的。最后,我们考虑了外磁场,用类似的线性方法研究了射频磁场激发的铁磁共振谱。研究表明：当钉扎层为倾斜各向异性时,共振磁场,共振线宽,进动频率以及自由层磁矩的平衡位置都可以通过改变直流电流密度的大小来调节。除了改变电流的大小和方向以为,我们还可以通过改变钉扎层的磁矩方向来改变磁系统中的能量吸收和发散。
Recently, spintronics has become a hot research field in condensed matter physics due to its abundant physical connotation and widely device application prospect. Since giant magnetoresistive(GMR) and tunneling magnetoresistive(TMR) effect are put forward, they have been widely applied in read-write heads, magnetic storage devices, magnetic detectors and microwave excitation etc. Especially, as the result of theoretical predictions in 1996 and later experimental verification of spin-transfer torque, it breaks the traditional method driven by the magnetic field to change or switch the magnetization direction of thin film materials. This new physical mechanism initially realizes the magnetization reversal or excites spin wave by using the spin-polarized current. In this thesis, we mainly investigate the ferromagnetic resonance in magnetic trilayers with a tilted spin polarizer theoretically.
First of all, we simply introduce the interaction energy and Landau-Lifshitz-Gilbert (LLG) magnetic dynamics equation. Then, under consideration of anisotropic energy and demagnetization energy, we spread the LLG equation including the spin torque term by the linearization method and obtain the current-and frequency-swept resonant spectra. At the same time, we analysis the dependences of the equilibrium position, resonant location and resonant linewidth on the current and the direction of the pinned magnetization. The influence of the dc current and the pinned magnetization on the power density is also discussed. The research shows that we can acquire the most energy pumping from the current to the free layer by optimizing the current density and the direction of the pinned magnetization in some regions. This is useful for improving the efficiency of current-driven microwave oscillation and current-induced magnetization reversal. Finally, we consider the static magnetic field and present a theoretical investigation of ferromagnetic resonance excited by rf magnetic field in magnetic trilayers with tilted anisotropy by the similar method. We find that the resonant magnetic field, the resonant linewidth, the precessional frequency, and the axis of the magnetization in the free layer are all changed by the spin-polarized current in the present of tilted pinned magnetization. Except for the direction and magnitude of spin polarized current, turning the direction of pinned magnetization provides a new choice of adjusting the pumping and dissipation of energy in the magnetic system.
首先,我们简单地介绍了铁磁材料中的相互作用能以及朗道-栗弗席兹-吉尔伯特(LLG)动力学方程。然后我们在只考虑各向异性能和退磁能的情形下,利用线性展开包含自旋转移矩的LLG动力学方程的方法,获得了电流和频率调节的铁磁共振谱,并且分析了平衡位置,共振位置和共振线宽随直流电流密度和钉扎层磁矩方向的变化关系,讨论了电流密度以及钉扎层磁矩方向对功率密度的影响。研究表明：通过选择合适的电流密度和钉扎层磁矩方向,可以从电流泵浦最大的能量到自由层。这一点对提高电流驱动的微波振荡器以及电流感应磁矩翻转的效率是非常有用的。最后,我们考虑了外磁场,用类似的线性方法研究了射频磁场激发的铁磁共振谱。研究表明：当钉扎层为倾斜各向异性时,共振磁场,共振线宽,进动频率以及自由层磁矩的平衡位置都可以通过改变直流电流密度的大小来调节。除了改变电流的大小和方向以为,我们还可以通过改变钉扎层的磁矩方向来改变磁系统中的能量吸收和发散。
Recently, spintronics has become a hot research field in condensed matter physics due to its abundant physical connotation and widely device application prospect. Since giant magnetoresistive(GMR) and tunneling magnetoresistive(TMR) effect are put forward, they have been widely applied in read-write heads, magnetic storage devices, magnetic detectors and microwave excitation etc. Especially, as the result of theoretical predictions in 1996 and later experimental verification of spin-transfer torque, it breaks the traditional method driven by the magnetic field to change or switch the magnetization direction of thin film materials. This new physical mechanism initially realizes the magnetization reversal or excites spin wave by using the spin-polarized current. In this thesis, we mainly investigate the ferromagnetic resonance in magnetic trilayers with a tilted spin polarizer theoretically.
First of all, we simply introduce the interaction energy and Landau-Lifshitz-Gilbert (LLG) magnetic dynamics equation. Then, under consideration of anisotropic energy and demagnetization energy, we spread the LLG equation including the spin torque term by the linearization method and obtain the current-and frequency-swept resonant spectra. At the same time, we analysis the dependences of the equilibrium position, resonant location and resonant linewidth on the current and the direction of the pinned magnetization. The influence of the dc current and the pinned magnetization on the power density is also discussed. The research shows that we can acquire the most energy pumping from the current to the free layer by optimizing the current density and the direction of the pinned magnetization in some regions. This is useful for improving the efficiency of current-driven microwave oscillation and current-induced magnetization reversal. Finally, we consider the static magnetic field and present a theoretical investigation of ferromagnetic resonance excited by rf magnetic field in magnetic trilayers with tilted anisotropy by the similar method. We find that the resonant magnetic field, the resonant linewidth, the precessional frequency, and the axis of the magnetization in the free layer are all changed by the spin-polarized current in the present of tilted pinned magnetization. Except for the direction and magnitude of spin polarized current, turning the direction of pinned magnetization provides a new choice of adjusting the pumping and dissipation of energy in the magnetic system.
引文
[1]Baibich M N, Broto J M, Fert A, et al. Giant Magnetoresistance of (001) Fe/(001)Cr Magnetic Superlattices. Phys Rev Lett,1988,61(21):2472-2475
[2]Slonczewski J C. Current-driven excitation of magnetic multilayers. J Magn Magn Mater,1996,159():L1-L7
[3]Berger L. Emission of spin waves by a magnetic multilayer traversed by a current. Physics Review B,1996,54(13):9353-9358
[4]Tsoi M, Jansen A G M, Bass J, et al. Excitation of a magnetic multilayer by an electric current. Phys Rev Lett,1998,80(19):4281-4284
[5]Katine J A, Albert F J, Buhrman R A, et al. Current-Driven Magnetization Reversal and Spin-Wave Excitations in Co/Cu/Co Pillars. Phys Rev Lett,2000, 84(14):3149-3152
[6]Tedrow P M, Meservey R. Spin-Dependent Tunneling into Ferromagnetic Nickel. Phys Rev Lett,1971,26(4):192-195
[7]Tedrow P M, Meservey R. Spin Polarization of Electrons Tunneling from Films of Fe, Co, Ni, and Gd. Phys Rev B,1973,7(1):318-326
[8]Julliere M. Tunneling between ferromagnetic films. Phys Lett A,1975,54(3): 225-226
[9]Igor Zutic, Jaroslav Fabian, Das Smama S. Spintronics:Fundamentals and applications. Rev Mod Phys,2004,76(2):323-409
[10]Grunberg P, Schreiber R, Pang Y. Layered Magnetic Structures:Evidence For Antiferromagnetic Coupling of Fe Layers across Cr Interlayers. Phys Rev Lett, 1986,57(19):2442-2445
[11]Mott N F.The electrical conductivity of transition metals. Proc Roy Soc London Ser,1936,153():699
[12]Parkin S S P, More N, Roche K P. Oscillations in exchange coupling and magnetoresistance in metallic superlattice structures:Co/Ru, Co/Cr, and Fe/Cr. Phys Rev Lett,1990,64(19):2304-2307
[13]Shinjo T, Yamamoto H. Large Magnetoresistance of Field-Induced Giant Ferrimagnetic Multilayers. Journal of the Physical Society of Japan,1990,59(): 3061-3064
[14]Yamamoto H, Okuyama T, Dohnomae H, et al. Magnetoresistance of multilayers with two magnetic components. J Magn Magn Mater,1991,99(1): 243-252
[15]Dieny B, Speriosu V S, Metin S, et al. Magnetotransport properties of magnetically soft spin-valve structures (invited). J Appl Phys,1991,69(8): 4774-4779
[16]Wolf S A, Awschalom D D, Buhrman R A, et al. Spintronics:A Spin-Based Electronics Vision for the Future. Science,2001,294():1488-149
[17]Miyazaki T, Tezuka N. Giant magnetic tunneling effect in Fe/Al2O3/Fe junction. J Magn Magn Mater,1995,139(3):L231-L234
[18]Terunobu Miyazaki, Nobuki Tezuka. Spin polarized tunneling in ferromagnet/insulator/ferromagnet junctions. J Magn Magn Mater,1995, 151(0304):403-410
[19]Stuart Parkin S P, Christian Kaiser, Alex Panchula, et al. Giant tunneling magnetoresistance at room temperature with MgO (100) tunnel barriers. Nat Mater,2004,3():862-867
[20]Yuasa S, Nagahama T, Fukushima A, et al. Giant room-temperature magnetoresistance in single-crystal Fe/MgO/Fe magnetic tunnel junctions. Nat Mater,2004,3():868-871
[21]张庆瑞.自旋电子传输与自旋电子学.物理双月刊,2000,26(6)：539-546
[22]孔令刚.韩汝琦磁随机存储器的研究进展.磁性材料及器件,2005,36(5)：7-9
[23]Gary Prinz A. Magnetoelectronics. Science,1998,282(27):1660-1663
[24]Gary Prinz A. Magnetoelectronics applications. J Magn Magn Mater,1999, 200():57-58
[25]Ralph D C, Stiles M D. Spin transfer torques. J Magn Magn Mater,2008, 320(7):1190-1216
[26]Berger L. Domain drag effect in the presence of variable magnetic field or variable transport current. J Appl Phys,1979,50(3):2137-2139
[27]Freitas P P, Berger L. Observation of s-d exchange force between domain walls and electric current in very thin Permalloy films. J Appl Phys,1985,57(4): 1266-1269
[28]Hung C Y, Berger L. Exchange forces between domain wall and electric current in permalloy films of variable thickness. J Appl Phys,1988,63(8):4276-4278
[29]Ono T, Ooka Y, Kasai S, et al. Magnetization reversal and electric transport in ferromagnetic nanowires. Mater Sci Eng B,2001,84(1-2):126-132
[30]Grollier Grollier J, Lacour D, Cros V, et al. Switching the magnetic configuration of a spin valve by current-induced domain wall motion. J Appl Phys,2002,92(8):4825-4827
[31]Klaui M, Vaz C A F, Bland J A C. Domain wall motion induced by spin polarized currents in ferromagnetic ring structures. Appl Phys Lett,2003,83(1): 105-107
[32]Tsoi M, Fontana Eand R S, Parkin S P. Magnetic domain wall motion triggered by an electric current. Appl Phys Lett,2003,83(1):2617-2679
[33]Xavier Waintal, Edward Myers B, Piet Brouwer W, et al. Role of spin-dependent interface scattering in generating current-induced torques in magnetic multilayers. Physics Review B,2000,62(18):12317-12327
[34]Albert F J, Emley N C, Myers E B, et al. Quantitative study of magnetization reversal by spin—polarized current in magnetic muhilayer nanopillars. Phys Rev Lett,2002,89(22):226802-1-226802-4
[35]Slonezewski J C. Currents, torques, and polarization factors in magnetic tunnel junctions. Phys Rev B,2005,71(2):024411-1-024411-10
[36]Katine J A, Eric Fullerton E. Device implications of spin-transfer torques. J Magn Magn Mater,2008,320(7):1217-1226
[37]Griffiths J H E. Anomalous High-frequency Resistance of Ferromagnetic Metals. Nature,1946,158():670-671
[38]Charles Kittel. Interpretation of Anomalous Larmor Frequencies in Ferromagnetic Resonance Experiment. Phys Rev,1947,71(4):270-271
[39]Michael Farle. Ferromagnetic resonance of ultrathin metallic layers. Rep Prog Phys,1998,61():755-826.
[40]Beaujour J M L, Chen W, Krycka K, et al. Ferromagnetic resonance study of sputtered Co/Ni multilayers. Eur Phys J B,2007,59():475-483
[41]Beaujour J M L, Kent A D, Abraham D W, et al. Ferromagnetic resonance study of polycrystalline Fe1-xVx alloy thin films. J Appl Phys,2008,103(7): 07B519-1-07B519-3
[42]Kakazei G N, Martin P P, Ruiz A, et al. Ferromagnetic resonance of ultrathin Co/Ag superlattices on Si(111). J Appl Phys,2008,103(7):07B527-1-07B527-3
[43]Cheng Wu, Amish Khalfan N. Carl Pettiford. Ferromagnetic resonance studies of surface and bulk spin-wave modes in a CoFe/PtMn/CoFe multilayer film. J Appl Phys,2008,103(7):07B525-1-07B525-3
[44]Farle M, Platow W, Kosubek E, et al. Magnetic anisotropy of Co/Cu(111) ultrathin films. Surf Sci,1999,439():146-152
[45]Mosendz O, Kardasz B, and Heinrich B. Ferromagnetic resonance and spin momentum exchange in crystalline magnetic ultrathin films in noncollinear configuration. J Appl Phys,2008,103(7):07B505-1-07B505-3
[46]Urban R, Woltersdorf G, Heinrich B. Gilbert Damping in Single and Multilayer Ultrathin Films:Role of Interfaces in Nonlocal Spin Dynamics. Phys Rev Lett, 2001,87():217204-1-217204-4
[47]Heinrich B, Woltersdorf G, Urban R, et al. Role of spin current in magnetic relaxations of metallic multilayer films. J Magn Magn Mater,2003,258(): 376-381
[48]Heinrich B, Woltersdorf G, Urban R, et al. Role of dynamic exchange coupling in magnetic relaxations of metallic multilayer films. J Appl Phys,2003,93(10): 7545-7550
[49]Mizukami S, Ando Y, Miyazaki T. Ferromagnetic resonance linewidth for NM/80NiFe/NM films (NM=Cu, Ta, Pd and Pt). J Magn Magn Mater,2001, 226():1640-1642
[50]Mizukami S, Ando Y, Miyazaki T. Effect of spin diffusion on Gilbert damping for a very thin permalloy layer in Cu/permalloy/Cu/Pt films. Physics Review B,2002,66(10):104413-1-104413-9
[51]Lubitz P, Cheng S F, Rachford F J. Increase of magnetic damping in thin polycrystalline Fe films induced by Cu/Fe overlayers. J Appl Phys,2003, 93(10):8283-8285
[52]Bret Heinrich, Yaroslav Tserkovnyak, GeorgWoltersdorf, et al. Dynamic Exchange Coupling in Magnetic Bilayers. Phys Rev Lett,2003,90(18): 187601-1-187601-4
[53]Lenz K, Tolinski T, Lindner J, et al. Evidence of spin-pumping effect in the ferromagnetic resonance of coupled trilayers. Phys Rev B,2004,69(14): 144422-1-144422-7
[54]Lindner J, K Baberschke. In situ ferromagnetic resonance:an ultimate tool to investigate the coupling in ultrathin magnetic films. J Phys:Condens Matter, 2003,15():R193-R232
[55]Lindner J, Baberschke K. Ferromagnetic resonance in coupled ultrathin films. J Phys:Condens Matter,2003,15():S465-S478
[56]Kardasz B, Mosendz O, Heinrich B, et al. Spin current studies in Fe/Ag,Au/Fe by ferromagnetic resonance and time-resolved magneto-optics. J Appl Phys, 2008,103(7):07C509-1-07C509-3
[57]Arne Brataas, Yaroslav Tserkovnyak, Gerrit. E W, et al. Spin battery operated by ferromagnetic resonance. Physics Review B,2002,66(6):060401-060404
[58]Costache M V, Sladkov M, Watts S M, et al. Electrical Detection of Spin Pumping due to the Precessing Magnetization of a Single Ferromagnet. Phys Rev Lett,2006,97(21):216603-1-216603-4
[59]Azevedo A, Vilela Leao L H, Rodriguez-Suarez R L, et al. dc effect in ferromagnetic resonance:Evidence of the spin-pumping effect? J Appl Phys, 2005,97(10):10C715-1-10C715-3
[60]Wang Xuhui, Gerrit Bauer E W, Bart Van Wees J, et al. Voltage Generation by Ferromagnetic Resonance at a Nonmagnet to Ferromagnet Contact. Phys Rev Lett,2006,97(21):216602-1-216602-4
[61]Hwee Kuan Leea, Zhimin Yuan. Studies of the magnetization reversal process driven by an oscillating field. J Appl Phys,2007,101(3):033903-1-033903-4
[62]Werner Scholz, Sharat Batra. Micromagnetic modeling of ferromagnetic resonance assisted switching. J Appl Phys,2008,103(7):07F539-1-07F539-3
[63]Tulapurkar A A, Suzuki Y, Fukushima A, et al. Spin-torque diode effect in magnetic tunnel junctions. Nature,2005,438():339-432
[64]Sankey J C, Braganca P M, Garcia A G F, et al. Spin-transfer-Driven Ferromagnetic Resonance of Indibidual Nanomagnets. Phys Rev Lett,2006, 96(22):227601-1-227601-4
[65]Fuchs G D, Sankey J C, Pribiag V S, et al. Spin-torque ferromagnetic resonance measurements of damping in nanomagnets. Appl Phys Lett,2007,91(8): 062507-1-062507-3
[66]Chen W, Beaujour L, Loubens G, et al. Spin-torque driven ferromagnetic resonance of Co/Ni synthetic layers in spin valves. Appl Phys L,2008,92(1): 012507-1-012507-3
[67]Chen W, Loubens G, Beaujour J M L, et al. Finite size effects on spin-torque driven ferromagnetic resonance in spin valves with a Co/Ni synthetic free layer. J Appl Phys,2008,103(7):07A502-1-07A502-3
[68]Torres L, Finocchio G, Lopez-Diaz L, et al. Micromagnetic modal analysis of spin-transfer-driven ferromagnetic resonance of individual nanomagnets. J Appl Phys,2007,101(9):09A502-1-09A502-3
[69]Haiwen Xi, Yiming Shi, Kai-Zhong Gao. Spin-current effect on ferromagnetic resonance in patterned magnetic thin film structures. J Appl Phys,2005,97(3): 033904-1-033904-5
[70]Joern Kupferschmidt N, Shaffique Adam, Piet W. Brouwer. Theory of spin-driven ferromagnetic resonance in a ferromagnet normal metal ferromagnet structure. Physics Review B,2006,74(13):134416-1-134416-6
[71]Alexey Kovalev A, Gerrit Bauer E W, Arne Brataas. Current-driven ferromagnetic resonance, mechanical torques, and rotary motion in magnetic nanostructures. Physics Review B,2007,75(1):014430-1-014430-12
[72]Michael Farle. Ferromagnetic resonance of ultrathin metallic layers. Rep Prog Phy,1998,61():755-826
[73]Kubota H, Fukushima A, Yakushiji K, et al. Quantitative measurement of voltage dependence of spin-transfer torque in MgO-based magnetic tunnel junctions. Nature physics,2008,4():37-41
[74]Sankey J C, Cui Y T, Buhrman R A, et al. Measurement of the Spin-Transfer-Torque Vector in Magnetic Tunnel Junctions. Nature physics, 2008,4():67-71
[75]Celinski Z, Urquhart K B, Heinrich B. Using ferromagnetic resonance to measure magnetic moments of ultrathin films. J Appl Phys,1997,81(8):4475
[76]Tsoi M, Tsoi V, Bass J, et al. Current-driven resonances in magnetic multilayers. Phys Rev Lett,2002,89(24):246803-1-246803-4
[77]Counil G, Joo Von Kim, Devolder T, et al. Spin wave contributions to the high-frequency magnetic response of thin films obtained with inductive methods. J Appl Phys,2004,95(10):5646-5652
[78]Cai J W, Kitakami O, Shimada Y. Isotropic soft magnetic properties of CoFeAlCu films with (111) orientation. J Appl Phys,1996,79(3):1625-1629
[79]Rado G T. Theory of ferromagnetic resonance and static magnetization in ultrathin crystals. Physical Review B,1982,26(1):295-304
[80]Guo J, Jalil M B A, Seongtae Bae, et al. Current-induced magnetization reversal mechanisms of pseudospin valves with perpendicular anisotropy. J Appl Phys,2007,102(9):093902-1-093902-5
[81]Garcia F, Fettar F, Auffret S, et al. Exchange-biased spin valves with perpendicular magnetic anisotropy based on (Co/Pt) multilayers. J Appl Phys, 2003,93(10):8397-8399
[82]Hao Meng, Jian-Ping Wang. Spin transfer in nanomagnetic devices with perpendicular anisotropy. Appl Phys Lett,2006,88(17):172506-1-172506-3
[83]Masahiko Nakayama, Tadashi Kai, Naoharu Shimomura, et al. Spin transfer switching in TbCoFe/CoFeB/MgO/CoFeB/TbCoFe magnetic tunnel junctions with perpendicular magnetic anisotropy. J Appl Phys,2008,103(7):07A710-1-07A710-3
[84]Shin S Cand, Agarwala A K. Magnetic anisotropy in TbFe thin films prepared at oblique incidence. J Appl Phys,1988,63(8):3645-3647
[85]Layadi A. A theoretical investigation of the effect of the oblique anisotropy axis on the ferromagnetic resonance linewidth. J Appl Phys,1999,86(8): 1625-1629
[86]Layadi A. Ferromagnetic resonance modes in single and coupled layers with oblique anisotropy axis. Phys Rev B,2001,63(17):174410-1-174410-8
[87]Kai Zhong Gao, Bertram H N. Magnetic recording configuration for densities beyond 1 Tb/in2 and data rates beyond 1 Gb/s. IEEE Trans Magn,2002,38(6): 3675-3683
[88]Wang J P, Zou Y Y, Hee C H, et al. Approaches to tilted magnetic recording for extremely high areal density. IEEE Trans Magn,2003,39(4):1930-1935
[89]Zou Y Y, Wang J P, Hee C H, et al. Tilted media in a perpendicular recording system for high areal density recording. Appl Phys Lett,2003,82(15): 2473-2475
[90]Wang J P. Tilting for the top. Nature Mater,2005,4():191-192
[91]Albrecht M, Hu G, Guhr I L, et al. Magnetic multilayers on nanospheres. Nature Materials,2005,4():203-204
[92]Singh A K, Yin J, Ko H Y Y, et al. Fabrication and characterization of granular-type (FePt/Fe3Pt)-and (FePt/fcc FePt)-tilted magnetic recording media. J Appl Phys,2006,99(8):08E704-1-08E704-3
[93]Takeshi Seki, Hiroyuki Tomita, Ashwin A, et al. Spin-transfer-torque-induced ferromagnetic resonance for Fe/Cr/Fe layers with an antiferromagnetic coupling field. Appl Phys Lett,2009,94(21):212502-1-212502-3
[94]Carpentieri M, Torres L. Micromagnetic computation of interface conductance of spin-transfer driven ferromagnetic resonance in nanopillar spin valves. J Appl Phys,2009,105(7):07D112-1-07D112-3
[95]Wang C, Cui Y T, Sun J Z, et al. Sensitivity of spin-torque diodes for frequency-tunable resonant microwave detection. J Appl Phys,2009,106(): 053905-1-053905-6
[96]Zha C L, Fang Y Y, Nogues J, et al. Improved magnetoresistance through spacer thickness optimization in tilted pseudo spin valves based on L10 (111)oriented FePtCu fixed layers. J Appl Phys,2009,106(5): 053909-1-053909-4
[97]Wang C, Cui Y T, Sun J Z, Katine J A, et al. Bias and angular dependence of spin-transfer torque in magnetic tunnel junctions. Phys Rev B,2009,79(22): 224416-1-224416-10
[98]Mangin S, Ravelosona D, Katine J A, et al. Current-induced magnetization reversal in nanopillars with perpendicular anisotropy. Nat Mater,2006,5(): 210-215
[99]Rachid Sbiaa, Randall Law, Ei-Leen Tan, et al. Spin transfer switching enhancement in perpendicular anisotropy magnetic tunnel junctions with a canted in-plane spin polarizer. J Appl Phys,2009,105(1):013910-1-013910-6
[100]Zhou Y, Zha C L, Bonetti S, et al. Spin-torque oscillator with tilted fixed layer magnetization. Appl Phys Lett,2008,92(26):262508-1-262508-3
[101]姜寿亭,李卫.凝聚态磁性物理.北京：科学出版社,2003：208-218
[102]Smith D O. Static and Dynamic Behavior of Thin Permalloy Films. J Appl Phys,1958,29(3):264-273
[2]Slonczewski J C. Current-driven excitation of magnetic multilayers. J Magn Magn Mater,1996,159():L1-L7
[3]Berger L. Emission of spin waves by a magnetic multilayer traversed by a current. Physics Review B,1996,54(13):9353-9358
[4]Tsoi M, Jansen A G M, Bass J, et al. Excitation of a magnetic multilayer by an electric current. Phys Rev Lett,1998,80(19):4281-4284
[5]Katine J A, Albert F J, Buhrman R A, et al. Current-Driven Magnetization Reversal and Spin-Wave Excitations in Co/Cu/Co Pillars. Phys Rev Lett,2000, 84(14):3149-3152
[6]Tedrow P M, Meservey R. Spin-Dependent Tunneling into Ferromagnetic Nickel. Phys Rev Lett,1971,26(4):192-195
[7]Tedrow P M, Meservey R. Spin Polarization of Electrons Tunneling from Films of Fe, Co, Ni, and Gd. Phys Rev B,1973,7(1):318-326
[8]Julliere M. Tunneling between ferromagnetic films. Phys Lett A,1975,54(3): 225-226
[9]Igor Zutic, Jaroslav Fabian, Das Smama S. Spintronics:Fundamentals and applications. Rev Mod Phys,2004,76(2):323-409
[10]Grunberg P, Schreiber R, Pang Y. Layered Magnetic Structures:Evidence For Antiferromagnetic Coupling of Fe Layers across Cr Interlayers. Phys Rev Lett, 1986,57(19):2442-2445
[11]Mott N F.The electrical conductivity of transition metals. Proc Roy Soc London Ser,1936,153():699
[12]Parkin S S P, More N, Roche K P. Oscillations in exchange coupling and magnetoresistance in metallic superlattice structures:Co/Ru, Co/Cr, and Fe/Cr. Phys Rev Lett,1990,64(19):2304-2307
[13]Shinjo T, Yamamoto H. Large Magnetoresistance of Field-Induced Giant Ferrimagnetic Multilayers. Journal of the Physical Society of Japan,1990,59(): 3061-3064
[14]Yamamoto H, Okuyama T, Dohnomae H, et al. Magnetoresistance of multilayers with two magnetic components. J Magn Magn Mater,1991,99(1): 243-252
[15]Dieny B, Speriosu V S, Metin S, et al. Magnetotransport properties of magnetically soft spin-valve structures (invited). J Appl Phys,1991,69(8): 4774-4779
[16]Wolf S A, Awschalom D D, Buhrman R A, et al. Spintronics:A Spin-Based Electronics Vision for the Future. Science,2001,294():1488-149
[17]Miyazaki T, Tezuka N. Giant magnetic tunneling effect in Fe/Al2O3/Fe junction. J Magn Magn Mater,1995,139(3):L231-L234
[18]Terunobu Miyazaki, Nobuki Tezuka. Spin polarized tunneling in ferromagnet/insulator/ferromagnet junctions. J Magn Magn Mater,1995, 151(0304):403-410
[19]Stuart Parkin S P, Christian Kaiser, Alex Panchula, et al. Giant tunneling magnetoresistance at room temperature with MgO (100) tunnel barriers. Nat Mater,2004,3():862-867
[20]Yuasa S, Nagahama T, Fukushima A, et al. Giant room-temperature magnetoresistance in single-crystal Fe/MgO/Fe magnetic tunnel junctions. Nat Mater,2004,3():868-871
[21]张庆瑞.自旋电子传输与自旋电子学.物理双月刊,2000,26(6)：539-546
[22]孔令刚.韩汝琦磁随机存储器的研究进展.磁性材料及器件,2005,36(5)：7-9
[23]Gary Prinz A. Magnetoelectronics. Science,1998,282(27):1660-1663
[24]Gary Prinz A. Magnetoelectronics applications. J Magn Magn Mater,1999, 200():57-58
[25]Ralph D C, Stiles M D. Spin transfer torques. J Magn Magn Mater,2008, 320(7):1190-1216
[26]Berger L. Domain drag effect in the presence of variable magnetic field or variable transport current. J Appl Phys,1979,50(3):2137-2139
[27]Freitas P P, Berger L. Observation of s-d exchange force between domain walls and electric current in very thin Permalloy films. J Appl Phys,1985,57(4): 1266-1269
[28]Hung C Y, Berger L. Exchange forces between domain wall and electric current in permalloy films of variable thickness. J Appl Phys,1988,63(8):4276-4278
[29]Ono T, Ooka Y, Kasai S, et al. Magnetization reversal and electric transport in ferromagnetic nanowires. Mater Sci Eng B,2001,84(1-2):126-132
[30]Grollier Grollier J, Lacour D, Cros V, et al. Switching the magnetic configuration of a spin valve by current-induced domain wall motion. J Appl Phys,2002,92(8):4825-4827
[31]Klaui M, Vaz C A F, Bland J A C. Domain wall motion induced by spin polarized currents in ferromagnetic ring structures. Appl Phys Lett,2003,83(1): 105-107
[32]Tsoi M, Fontana Eand R S, Parkin S P. Magnetic domain wall motion triggered by an electric current. Appl Phys Lett,2003,83(1):2617-2679
[33]Xavier Waintal, Edward Myers B, Piet Brouwer W, et al. Role of spin-dependent interface scattering in generating current-induced torques in magnetic multilayers. Physics Review B,2000,62(18):12317-12327
[34]Albert F J, Emley N C, Myers E B, et al. Quantitative study of magnetization reversal by spin—polarized current in magnetic muhilayer nanopillars. Phys Rev Lett,2002,89(22):226802-1-226802-4
[35]Slonezewski J C. Currents, torques, and polarization factors in magnetic tunnel junctions. Phys Rev B,2005,71(2):024411-1-024411-10
[36]Katine J A, Eric Fullerton E. Device implications of spin-transfer torques. J Magn Magn Mater,2008,320(7):1217-1226
[37]Griffiths J H E. Anomalous High-frequency Resistance of Ferromagnetic Metals. Nature,1946,158():670-671
[38]Charles Kittel. Interpretation of Anomalous Larmor Frequencies in Ferromagnetic Resonance Experiment. Phys Rev,1947,71(4):270-271
[39]Michael Farle. Ferromagnetic resonance of ultrathin metallic layers. Rep Prog Phys,1998,61():755-826.
[40]Beaujour J M L, Chen W, Krycka K, et al. Ferromagnetic resonance study of sputtered Co/Ni multilayers. Eur Phys J B,2007,59():475-483
[41]Beaujour J M L, Kent A D, Abraham D W, et al. Ferromagnetic resonance study of polycrystalline Fe1-xVx alloy thin films. J Appl Phys,2008,103(7): 07B519-1-07B519-3
[42]Kakazei G N, Martin P P, Ruiz A, et al. Ferromagnetic resonance of ultrathin Co/Ag superlattices on Si(111). J Appl Phys,2008,103(7):07B527-1-07B527-3
[43]Cheng Wu, Amish Khalfan N. Carl Pettiford. Ferromagnetic resonance studies of surface and bulk spin-wave modes in a CoFe/PtMn/CoFe multilayer film. J Appl Phys,2008,103(7):07B525-1-07B525-3
[44]Farle M, Platow W, Kosubek E, et al. Magnetic anisotropy of Co/Cu(111) ultrathin films. Surf Sci,1999,439():146-152
[45]Mosendz O, Kardasz B, and Heinrich B. Ferromagnetic resonance and spin momentum exchange in crystalline magnetic ultrathin films in noncollinear configuration. J Appl Phys,2008,103(7):07B505-1-07B505-3
[46]Urban R, Woltersdorf G, Heinrich B. Gilbert Damping in Single and Multilayer Ultrathin Films:Role of Interfaces in Nonlocal Spin Dynamics. Phys Rev Lett, 2001,87():217204-1-217204-4
[47]Heinrich B, Woltersdorf G, Urban R, et al. Role of spin current in magnetic relaxations of metallic multilayer films. J Magn Magn Mater,2003,258(): 376-381
[48]Heinrich B, Woltersdorf G, Urban R, et al. Role of dynamic exchange coupling in magnetic relaxations of metallic multilayer films. J Appl Phys,2003,93(10): 7545-7550
[49]Mizukami S, Ando Y, Miyazaki T. Ferromagnetic resonance linewidth for NM/80NiFe/NM films (NM=Cu, Ta, Pd and Pt). J Magn Magn Mater,2001, 226():1640-1642
[50]Mizukami S, Ando Y, Miyazaki T. Effect of spin diffusion on Gilbert damping for a very thin permalloy layer in Cu/permalloy/Cu/Pt films. Physics Review B,2002,66(10):104413-1-104413-9
[51]Lubitz P, Cheng S F, Rachford F J. Increase of magnetic damping in thin polycrystalline Fe films induced by Cu/Fe overlayers. J Appl Phys,2003, 93(10):8283-8285
[52]Bret Heinrich, Yaroslav Tserkovnyak, GeorgWoltersdorf, et al. Dynamic Exchange Coupling in Magnetic Bilayers. Phys Rev Lett,2003,90(18): 187601-1-187601-4
[53]Lenz K, Tolinski T, Lindner J, et al. Evidence of spin-pumping effect in the ferromagnetic resonance of coupled trilayers. Phys Rev B,2004,69(14): 144422-1-144422-7
[54]Lindner J, K Baberschke. In situ ferromagnetic resonance:an ultimate tool to investigate the coupling in ultrathin magnetic films. J Phys:Condens Matter, 2003,15():R193-R232
[55]Lindner J, Baberschke K. Ferromagnetic resonance in coupled ultrathin films. J Phys:Condens Matter,2003,15():S465-S478
[56]Kardasz B, Mosendz O, Heinrich B, et al. Spin current studies in Fe/Ag,Au/Fe by ferromagnetic resonance and time-resolved magneto-optics. J Appl Phys, 2008,103(7):07C509-1-07C509-3
[57]Arne Brataas, Yaroslav Tserkovnyak, Gerrit. E W, et al. Spin battery operated by ferromagnetic resonance. Physics Review B,2002,66(6):060401-060404
[58]Costache M V, Sladkov M, Watts S M, et al. Electrical Detection of Spin Pumping due to the Precessing Magnetization of a Single Ferromagnet. Phys Rev Lett,2006,97(21):216603-1-216603-4
[59]Azevedo A, Vilela Leao L H, Rodriguez-Suarez R L, et al. dc effect in ferromagnetic resonance:Evidence of the spin-pumping effect? J Appl Phys, 2005,97(10):10C715-1-10C715-3
[60]Wang Xuhui, Gerrit Bauer E W, Bart Van Wees J, et al. Voltage Generation by Ferromagnetic Resonance at a Nonmagnet to Ferromagnet Contact. Phys Rev Lett,2006,97(21):216602-1-216602-4
[61]Hwee Kuan Leea, Zhimin Yuan. Studies of the magnetization reversal process driven by an oscillating field. J Appl Phys,2007,101(3):033903-1-033903-4
[62]Werner Scholz, Sharat Batra. Micromagnetic modeling of ferromagnetic resonance assisted switching. J Appl Phys,2008,103(7):07F539-1-07F539-3
[63]Tulapurkar A A, Suzuki Y, Fukushima A, et al. Spin-torque diode effect in magnetic tunnel junctions. Nature,2005,438():339-432
[64]Sankey J C, Braganca P M, Garcia A G F, et al. Spin-transfer-Driven Ferromagnetic Resonance of Indibidual Nanomagnets. Phys Rev Lett,2006, 96(22):227601-1-227601-4
[65]Fuchs G D, Sankey J C, Pribiag V S, et al. Spin-torque ferromagnetic resonance measurements of damping in nanomagnets. Appl Phys Lett,2007,91(8): 062507-1-062507-3
[66]Chen W, Beaujour L, Loubens G, et al. Spin-torque driven ferromagnetic resonance of Co/Ni synthetic layers in spin valves. Appl Phys L,2008,92(1): 012507-1-012507-3
[67]Chen W, Loubens G, Beaujour J M L, et al. Finite size effects on spin-torque driven ferromagnetic resonance in spin valves with a Co/Ni synthetic free layer. J Appl Phys,2008,103(7):07A502-1-07A502-3
[68]Torres L, Finocchio G, Lopez-Diaz L, et al. Micromagnetic modal analysis of spin-transfer-driven ferromagnetic resonance of individual nanomagnets. J Appl Phys,2007,101(9):09A502-1-09A502-3
[69]Haiwen Xi, Yiming Shi, Kai-Zhong Gao. Spin-current effect on ferromagnetic resonance in patterned magnetic thin film structures. J Appl Phys,2005,97(3): 033904-1-033904-5
[70]Joern Kupferschmidt N, Shaffique Adam, Piet W. Brouwer. Theory of spin-driven ferromagnetic resonance in a ferromagnet normal metal ferromagnet structure. Physics Review B,2006,74(13):134416-1-134416-6
[71]Alexey Kovalev A, Gerrit Bauer E W, Arne Brataas. Current-driven ferromagnetic resonance, mechanical torques, and rotary motion in magnetic nanostructures. Physics Review B,2007,75(1):014430-1-014430-12
[72]Michael Farle. Ferromagnetic resonance of ultrathin metallic layers. Rep Prog Phy,1998,61():755-826
[73]Kubota H, Fukushima A, Yakushiji K, et al. Quantitative measurement of voltage dependence of spin-transfer torque in MgO-based magnetic tunnel junctions. Nature physics,2008,4():37-41
[74]Sankey J C, Cui Y T, Buhrman R A, et al. Measurement of the Spin-Transfer-Torque Vector in Magnetic Tunnel Junctions. Nature physics, 2008,4():67-71
[75]Celinski Z, Urquhart K B, Heinrich B. Using ferromagnetic resonance to measure magnetic moments of ultrathin films. J Appl Phys,1997,81(8):4475
[76]Tsoi M, Tsoi V, Bass J, et al. Current-driven resonances in magnetic multilayers. Phys Rev Lett,2002,89(24):246803-1-246803-4
[77]Counil G, Joo Von Kim, Devolder T, et al. Spin wave contributions to the high-frequency magnetic response of thin films obtained with inductive methods. J Appl Phys,2004,95(10):5646-5652
[78]Cai J W, Kitakami O, Shimada Y. Isotropic soft magnetic properties of CoFeAlCu films with (111) orientation. J Appl Phys,1996,79(3):1625-1629
[79]Rado G T. Theory of ferromagnetic resonance and static magnetization in ultrathin crystals. Physical Review B,1982,26(1):295-304
[80]Guo J, Jalil M B A, Seongtae Bae, et al. Current-induced magnetization reversal mechanisms of pseudospin valves with perpendicular anisotropy. J Appl Phys,2007,102(9):093902-1-093902-5
[81]Garcia F, Fettar F, Auffret S, et al. Exchange-biased spin valves with perpendicular magnetic anisotropy based on (Co/Pt) multilayers. J Appl Phys, 2003,93(10):8397-8399
[82]Hao Meng, Jian-Ping Wang. Spin transfer in nanomagnetic devices with perpendicular anisotropy. Appl Phys Lett,2006,88(17):172506-1-172506-3
[83]Masahiko Nakayama, Tadashi Kai, Naoharu Shimomura, et al. Spin transfer switching in TbCoFe/CoFeB/MgO/CoFeB/TbCoFe magnetic tunnel junctions with perpendicular magnetic anisotropy. J Appl Phys,2008,103(7):07A710-1-07A710-3
[84]Shin S Cand, Agarwala A K. Magnetic anisotropy in TbFe thin films prepared at oblique incidence. J Appl Phys,1988,63(8):3645-3647
[85]Layadi A. A theoretical investigation of the effect of the oblique anisotropy axis on the ferromagnetic resonance linewidth. J Appl Phys,1999,86(8): 1625-1629
[86]Layadi A. Ferromagnetic resonance modes in single and coupled layers with oblique anisotropy axis. Phys Rev B,2001,63(17):174410-1-174410-8
[87]Kai Zhong Gao, Bertram H N. Magnetic recording configuration for densities beyond 1 Tb/in2 and data rates beyond 1 Gb/s. IEEE Trans Magn,2002,38(6): 3675-3683
[88]Wang J P, Zou Y Y, Hee C H, et al. Approaches to tilted magnetic recording for extremely high areal density. IEEE Trans Magn,2003,39(4):1930-1935
[89]Zou Y Y, Wang J P, Hee C H, et al. Tilted media in a perpendicular recording system for high areal density recording. Appl Phys Lett,2003,82(15): 2473-2475
[90]Wang J P. Tilting for the top. Nature Mater,2005,4():191-192
[91]Albrecht M, Hu G, Guhr I L, et al. Magnetic multilayers on nanospheres. Nature Materials,2005,4():203-204
[92]Singh A K, Yin J, Ko H Y Y, et al. Fabrication and characterization of granular-type (FePt/Fe3Pt)-and (FePt/fcc FePt)-tilted magnetic recording media. J Appl Phys,2006,99(8):08E704-1-08E704-3
[93]Takeshi Seki, Hiroyuki Tomita, Ashwin A, et al. Spin-transfer-torque-induced ferromagnetic resonance for Fe/Cr/Fe layers with an antiferromagnetic coupling field. Appl Phys Lett,2009,94(21):212502-1-212502-3
[94]Carpentieri M, Torres L. Micromagnetic computation of interface conductance of spin-transfer driven ferromagnetic resonance in nanopillar spin valves. J Appl Phys,2009,105(7):07D112-1-07D112-3
[95]Wang C, Cui Y T, Sun J Z, et al. Sensitivity of spin-torque diodes for frequency-tunable resonant microwave detection. J Appl Phys,2009,106(): 053905-1-053905-6
[96]Zha C L, Fang Y Y, Nogues J, et al. Improved magnetoresistance through spacer thickness optimization in tilted pseudo spin valves based on L10 (111)oriented FePtCu fixed layers. J Appl Phys,2009,106(5): 053909-1-053909-4
[97]Wang C, Cui Y T, Sun J Z, Katine J A, et al. Bias and angular dependence of spin-transfer torque in magnetic tunnel junctions. Phys Rev B,2009,79(22): 224416-1-224416-10
[98]Mangin S, Ravelosona D, Katine J A, et al. Current-induced magnetization reversal in nanopillars with perpendicular anisotropy. Nat Mater,2006,5(): 210-215
[99]Rachid Sbiaa, Randall Law, Ei-Leen Tan, et al. Spin transfer switching enhancement in perpendicular anisotropy magnetic tunnel junctions with a canted in-plane spin polarizer. J Appl Phys,2009,105(1):013910-1-013910-6
[100]Zhou Y, Zha C L, Bonetti S, et al. Spin-torque oscillator with tilted fixed layer magnetization. Appl Phys Lett,2008,92(26):262508-1-262508-3
[101]姜寿亭,李卫.凝聚态磁性物理.北京：科学出版社,2003：208-218
[102]Smith D O. Static and Dynamic Behavior of Thin Permalloy Films. J Appl Phys,1958,29(3):264-273