巨磁阻模型中热产生分布的理论研究
Theory of the Heat Generation in Giant Magnetoresistance Model
摘要: 自旋热效应是最近出现的研究领域，内容围绕于自旋与热流的相互作用，引起了广泛的讨论。由于热效应对纳米尺度的电子器件的电学、热学和磁学性能的研究有重要的意义，磁性多层结构中存在的热产生是一个不容忽视的问题。我们用基于玻尔兹曼方程的宏观近似，在理论上研究了磁性多层结构中由于输运导致热产生。在磁性多层结构中通入电流后，除了会产生普通材料的焦耳热外，还存在来自于自旋积累的额外热产生。我们用巨磁阻模型计算了热产生分布的表达式，并比较了反平行结构和平行结构中自旋相关热产生分布和大小的差异。分析结果表明，在反平行结构中，自旋相关热产生比较多，对材料的影响比较大，而平行结构中自旋相关热产生比较少。所以，当两个铁磁层磁化方向变化时，装置中的热产生也发生明显的变化，是一种类巨磁阻效应。
Abstract: Spin caloritronics is a newly-explored research field concerning mainly the interaction of spin and heat, and has attracted extensive research interests recently. Heat generation in magnetic multilayers is a serious problem, because it has significant effects on the electric, thermal, and magnetic properties of nanoscale electronic devices. Here we study theoretically the heat generation due to spin transport in magnetic multilayers by using a macroscopic approach based on the Boltzmann equation. There exists extra heat generation due to spin accumulation besides the nominal Joule heat, when a current flows through the magnetic multilayers. On the basis of the giant magnetoresistance (GMR) model, we derived the expressions for the distribution of heat generation. We also compared the distribution and magnitude of the heat generation in an-tiparallel (AP) and parallel (P) alignments. Our analysis shows that the AP alignment leads to larger heat generation than the P alignment. Therefore, the heat generation in the structure changes dramatically with the relative alignment of the two ferromagnetic layers, which is simi-lar to the GMR effect.
文章引用：张小雪. 巨磁阻模型中热产生分布的理论研究[J]. 现代物理, 2017, 7(2): 25-31. https://doi.org/10.12677/MP.2017.72004

参考文献

[1] Baibich, M.N., Broto, J.M., Fert, A., et al. (1988) Giant Magnetoresistance of (001)Fe/(001)Cr Magnetic Superlattices. Physical Review Letters, 61, 2472-2475. [Google Scholar] [CrossRef] 
[2] Valet, T. and Fert, A. (1993) Theory of the Perpendicular Magnetiresistance in Magnetic Multilayers. Physical Review B, 48, 7099-7113. [Google Scholar] [CrossRef] 
[3] Bauer, G.E., Saitoh, E. and van Wees, B.J. (2012) Spin Caloritronics. Nature Materals, 11, 391-399. [Google Scholar] [CrossRef] [PubMed]
[4] Uchida, K., Takahashi, S., Harii, K., et al. (2008) Observation of the Spin Seebeck Effect. Nature, 455, 778-781. [Google Scholar] [CrossRef] [PubMed]
[5] Mu, C., Hu, S., Wang, J., et al. (2013) Thermo-Electric Effect in a Nano-Sized Crossed Permalloy/Cu Junction under High Bias Current. Applied Physics Letters, 103, Article ID: 132408. [Google Scholar] [CrossRef] 
[6] Dejene, F.K., Flipse, J. and van Wees, B.J. (2014) Verification of the Thomson-Onsager Reciprocity Relation for Spin Caloritronics. Physical Review B, 90, Article ID: 180402. [Google Scholar] [CrossRef] 
[7] Bakker, F.L., Slachter, A., Adam, J.P., et al. (2010) Interplay of Peltier and Seebeck Effects in Nanoscale Nonlocal Spin Valves. Physical Review Letters, 105, Article ID: 136601. [Google Scholar] [CrossRef] 
[8] Erekhinsky, M., Casanova, F.I., Schuller, I.K., et al. (2012) Spin-Dependent Seebeck Effect in Non-Local Spin Valve Devices. Applied Physics Letters, 100, Article ID: 212401. [Google Scholar] [CrossRef] 
[9] Krause, S., Herzog, G., Schlenhoff, A., et al. (2011) Joule Heating and Spin-Transfer Torque Investigated on the Atomic Scale Using a Spin-Polarized Scanning Tunneling Microscope. Physical Review Letters, 107, Article ID: 186601. [Google Scholar] [CrossRef] 
[10] Jeon, K.R., Min, B.C., Park, S.Y., et al. (2013) Thermal Spin Injection and Accumulation in CoFe/MgO Tunnel Contacts to n-Type Si through Seebeck Spin Tunneling. Applied Physics Letters, 103, Article ID: 142401. [Google Scholar] [CrossRef] 
[11] Dankert, A. and Dash, S.P. (2013) Thermal Creation of Electron Spin Polarization in n-Type Silicon. Applied Physics Letters, 103, Article ID: 242405. [Google Scholar] [CrossRef] 
[12] Foros, J., Brataas, A., Bauer, G.E., et al. (2009) Noise and Dissipation in Magnetoelectronic Nanostructures. Physical Review B, 79, Article ID: 214407. [Google Scholar] [CrossRef] 
[13] Léonard, F. (2011) Reduced Joule Heating in Nanowires. Applied Physics Letters, 98, Article ID: 103101. [Google Scholar] [CrossRef] 
[14] Tulapurkar, A.A. and Suzuki, Y. (2011) Boltzmann Approach to Dissipation Produced by a Spin-Polarized Current. Physical Review B, 83, Article ID: 012401. [Google Scholar] [CrossRef] 
[15] Taniguchi, T. and Saslow, W.M. (2014) Dissipation Due to Pure Spin-Current Generated by Spin Pumping. Physical Review B, 90, Article ID: 214407. [Google Scholar] [CrossRef] 
[16] Taniguchi, T. and Saslow, W.M. (2016) Heat Production by Diffusion of Pure Spin Current. Journal of Magnetism and Magnetic Materials, 400, 168-170. [Google Scholar] [CrossRef]