标题： 补偿半金属ScSb中的能斯脱功率因子和优值系数 显示英文标题

标题： Nernst power factor and figure of merit in compensated semimetal ScSb

摘要： 近年来，由于拓扑半金属具有增强的能斯特效应，它们已成为固态热磁制冷机的有力候选者。 这种增强来源于与拓扑能带相关的贝里曲率诱导的反常能斯特系数以及由电子-空穴补偿产生的正常能斯特效应的综合贡献。 通常，在拓扑半金属中，这两种效应相互交织，使得独立评估它们变得困难。 在这里，我们报道了在电子-空穴补偿的半金属ScSb（具有拓扑平凡的电子能带结构）中观察到的高能斯特效应。 值得注意的是，我们在ScSb中发现了一个高的最大能斯特功率因子，即$PF_N \sim 35 \times 10^{-4}$ W m$^{-1}$ K$^{-2}$。 Nernst温差电动势（$S_{xy}$）在12K和14T时出现峰值$\sim$ 47 $\mu$V/K，得出Nernst品质因子（$z_N$）为$\sim 28 \times 10^{-4}$ K$^{-1}$。 值得注意的是，尽管ScSb的电子能带结构简单，但其 $PF_N$ 和 $z_N$ 值与具有狄拉克带色散的拓扑半金属中的值相当。 ScSb中大热电势信号的起源通过霍尔电阻测量、角分辨光电子能谱（ARPES）和密度泛函理论（DFT）计算，被归因于电子和空穴载流子的良好补偿。 显示英文摘要

摘要： Recently, topological semimetals have emerged as strong candidates for solid state thermomagnetic refrigerators due to their enhanced Nernst effect. This enhancement arises from the combined contributions of the Berry curvature induced anomalous Nernst coefficient associated with topological bands and the normal Nernst effect resulting from synergistic electron-hole compensation. Generally, these two effects are intertwined in topological semimetals, making it challenging to evaluate them independently. Here, we report the observation of high Nernst effect in the electron hole compensated semimetal ScSb with topologically trivial electronic band structures. Remarkably, we find a high maximum Nernst power factor of $PF_N \sim 35 \times 10^{-4}$ W m$^{-1}$ K$^{-2}$ in ScSb. The Nernst thermopower ($S_{xy}$) exhibits a peak of $\sim$ 47 $\mu$V/K at 12 K and 14 T, yielding a Nernst figure of merit ($z_N$) of $\sim 28 \times 10^{-4}$ K$^{-1}$. Notably, despite its trivial electronic band structure, both the $PF_N$ and $z_N$ values of ScSb are comparable to those observed in topological semimetals with Dirac band dispersions. The origin of the large Nernst signal in ScSb is explained by well compensated electron and hole carriers, through Hall resistivity measurements, angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT) calculations.