Department of Physics, University of Hamburg, Jungiusstrasse 11A, 20355 Hamburg, Germany.
Science. 2019 Mar 8;363(6431):1065-1067. doi: 10.1126/science.aat7234. Epub 2019 Mar 7.
The tunneling of spin-polarized electrons across a magnetic tunnel junction driven by a temperature gradient is a fundamental process for the thermal control of electron spin transport. We experimentally investigated the atomic-scale details of this magneto-Seebeck tunneling by placing a magnetic probe tip in close proximity to a magnetic sample at cryogenic temperature, with a vacuum as the tunneling barrier. Heating the tip and measuring the thermopower of the junction while scanning across the spin texture of the sample lead to spin-resolved Seebeck coefficients that can be mapped at atomic-scale lateral resolution. We propose a spin detector for spintronics applications that is driven solely by waste heat, using magneto-Seebeck tunneling to convert spin information into a voltage that can be used for further data processing.
自旋极化电子在磁场隧道结中的隧穿过程受到温度梯度的驱动，这是电子自旋输运热控制的基本过程。我们通过将磁性探针尖端放置在低温磁性样品附近，并在真空作为隧道势垒的情况下，实验性地研究了这种磁塞贝克隧穿的原子尺度细节。通过加热尖端并在扫描样品的自旋结构时测量结的热功率，得到了可以在原子尺度横向分辨率下绘制的自旋分辨塞贝克系数。我们提出了一种用于自旋电子学应用的自旋探测器，该探测器仅由余热驱动，利用磁塞贝克隧穿将自旋信息转换为电压，可用于进一步的数据处理。
