﻿ 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

Modern Physics
Vol.07 No.02(2017), Article ID:19890,7 pages
10.12677/MP.2017.72004

Theory of the Heat Generation in Giant Magnetoresistance Model

Xiaoxue Zhang

Beijing Technology and Business University, Beijing

Received: Feb. 24th, 2017; accepted: Mar. 12th, 2017; published: Mar. 15th, 2017

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 antiparallel (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 similar to the GMR effect.

Keywords:Giant Magnetoresistance Model, Spin-Dependent Heat Generation, Antiparallel Configuration, Parallel Configuration

1. 引言

2. 热产生分布表达式的简化

(1)

(2)

(3)

(4)

(5)

(6)

Tulapurkar等人用玻尔兹曼输运方程计算了自旋流产生的能量损耗 [14] ，给出了单位时间内热产生密度随位置变化的表达式。稳态时，单位时间内的热产生密度为

(7)

(8)

3. 两种结构中自旋相关热产生的比较

(9)

(10)

(11)

(12)

3.1. 反平行结构

3.2. 平行结构

Figure 1. Spin-dependent heat generation per unit time in antiparallel configuration

(a) (b)

Figure 2. Spin-dependent heat generation per unit time in parallel configuration. The thickness of nonmagnetic layer is (a) 60 nm, (b) 600 nm

4. 结论

Theory of the Heat Generation in Giant Magnetoresistance Model[J]. 现代物理, 2017, 07(02): 25-31. http://dx.doi.org/10.12677/MP.2017.72004

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