The Seebeck effect explains the generation of electric voltage as a result of a temperature gradient. Its efficiency, defined as the ratio of the generated electric voltage to the temperature difference, is sensitive to local inhomogeneities that alter the scattering rate and the density of the conduction electrons. Spin-polarized Seebeck tunneling generates a distinct thermovoltage in spin-up and spin-down charge transport channels, which, as a key to spin caloritronics, focuses on transport phenomena related to spin and heat. Here, we report spatially resolved measurement of the spin-dependent thermovoltage in a tunneling junction formed by ferromagnetic Co nanoislands and a Ni tip using spin-dependent scanning tunneling thermovoltage microscopy (SP-STV_thM). We resolve the nanoscale thermoelectric powers with respect to spin polarization, nanoisland size, stacking order of Co layers on a Cu substrate, and local sample heterogeneities. The observed thermally generated spin voltages are supported by first-principles and model calculations.

中文翻译：

---

纳米岛的自旋相关热电功率。

塞贝克效应解释了由于温度梯度而产生的电压。它的效率（定义为所产生的电压与温度差的比）对局部不均匀性敏感，这些不均匀性会改变散射速率和导电电子的密度。自旋极化的塞贝克隧穿在自旋向上和自旋向下的电荷传输通道中产生不同的热电压，这是自旋量热电子学的关键，重点在于与自旋和热有关的传输现象。在这里，我们报告使用自旋相关扫描隧穿热电压显微镜（SP-STV _th），对由铁磁Co纳米岛和Ni尖端形成的隧道结中的自旋相关热电压进行空间分辨测量M）。我们解决了关于自旋极化，纳米岛尺寸，Cu基板上Co层的堆叠顺序以及局部样品异质性的纳米级热电势。第一性原理和模型计算支持了观察到的热产生的自旋电压。