Thermal gradient driven enhancement of pure spin current at room temperature in nonlocal spin transport devices
Thermal gradient driven enhancement of pure spin current at room temperature in nonlocal spin transport devices
复制标题
非局域自旋输运器件中室温下纯自旋电流的热梯度驱动增强
DOI：
10.1103/physrevb.88.184407
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发表时间：
2013
影响因子：
3.7
通讯作者：
S. Hu and T. Kimura
中科院分区：
文献类型：
--
作者：
S. R. Bakaul;S. Hu and T. Kimura
我们发现，在横向配置的铁磁/铁磁（FM/NM）混合结构的结设计显着影响高偏置电流下的自旋输运。FM和NM之间的热导率失配以及界面处的不均匀电流分布产生反向温度梯度，这大大降低了热自旋注入效率。界面处温度梯度的均匀性是决定热自旋电流产生效率的关键因素。实验结果与理论模型[Y. Takezoe，Phys. Rev. B 82，094451（2010）PRBMDO 1098 -012110.1103/PhysRevB.82.094451]中所述，自旋弛豫与温度的二阶空间导数成比例。
We show that the junction design in the laterally configured ferromagnetic/nonmagnetic (FM/NM) hybrid structure significantly affects the spin transport under high-bias current. The thermal conductivity mismatch between FM and NM and the inhomogeneous current distribution at the interface produce a reversed temperature gradient, which drastically reduces the thermal spin injection efficiency. The homogeneity in the temperature gradient at the interface is a crucial factor in determining the efficiency of the thermal spin current generation. The experimental results show excellent agreement with the theoretical model [Y. Takezoe , Phys. Rev. B 82, 094451 (2010)PRBMDO1098-012110.1103/PhysRevB.82.094451] that the spin relaxation is proportional to the second spatial derivative of the temperature.