We report the study of the thermoelectric properties of layered ternary telluride ${\mathrm{Nb}}_3{\mathrm{SiTe}}_6$. The temperature dependence of the thermoelectric power (TEP) evolves from nonlinear to linear when the thickness of the devices is reduced, consistent with the suppression of electron-phonon interaction caused by quantum confinement. The magnitude of TEP strongly depends on the hole density. It increases with decreasing hole density when the hole density is low, as observed in ionic-liquid-gated thin flakes. However, the device with the largest hole density possesses the highest TEP. Theoretical analysis suggests that the high TEP in the device with the largest hole density can be ascribed to the phonon-mediated intervalley scatterings. The highest TEP reaches $\sim 230\mu \mathrm{V}/\mathrm{K}$ at 370 K while the electrical resistivity of the device is maintained below $1.5\mathrm{m}\mathrm{\Omega }\mathrm{cm}$. Therefore, a large power factor PF $\sim 36\mu \mathrm{W}\mathrm{c}{\mathrm{m}}^{-1}{\mathrm{K}}^{-2}$ comparable to the record values reported in $p$-type materials is obtained.

中文翻译：

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层状三元碲化物Nb3SiTe6的热电性质

我们报告了层状三元碲化物热电性质的研究 ${铌}_3{\mathrm{现场}}_6$。当减小器件的厚度时，热电功率（TEP）的温度依赖性从非线性演变为线性，这与抑制量子限制引起的电子-声子相互作用是一致的。TEP的大小很大程度上取决于孔的密度。如在离子液体门控薄片中观察到的那样，当孔密度低时，它随着孔密度的降低而增加。但是，具有最大孔密度的设备具有最高的TEP。理论分析表明，具有最大空穴密度的器件中的高TEP可以归因于声子介导的音程散射。最高TEP达到$〜230\mu \mathrm{V}/\mathrm{ķ}$ 保持在370 K $1.5\mathrm{米}\mathrm{\Omega }\mathrm{厘米}$。因此，功率因数PF大$〜36\mu \mathrm{w\; ^}\mathrm{C}{\mathrm{米}}^{-\mathrm{1个}}{\mathrm{ķ}}^{-2}$ 与报告中的记录值相当 $p$获得类型的材料。