We present an experimental study of the thermo emf of a two-dimensional electron-hole system in a 21 nm HgTe quantum well in the presence of magnetic field. The first experimental observation of Nernst-Ettingshausen effect in a 2D semimetal is reported. The comparison between theory and experiment shows that the thermo emf is determined by two contributions: the diffusion and the phonon drag, with the latter contribution several times greater than the first. The conclusion is drawn about the important role of electron-hole scattering in the formation of both thermoelectric power mechanisms.

中文翻译：

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HgTe量子阱中存在磁场的二维电子-空穴系统中的热电动势。扩散作用和声子拖曳作用

我们提出了在存在磁场的情况下在21 nm HgTe量子阱中二维电子-空穴系统热电动势的实验研究。据报道，在2D半金属中能斯特（Nernst-Ettingshausen）效应的首次实验观察。理论与实验的比较表明，热电动势由两个因素决定：扩散和声子阻力，后者的贡献是第一个的几倍。结论得出电子空穴散射在两种热电机理中的重要作用。