论文标题
来自AB-Initio计算的四频$ _5 $的四波段模型中的光学电导率和电阻率
Optical conductivity and resistivity in a four-band model for ZrTe$_5$ from ab-initio calculations
论文作者
论文摘要
zrte $ _5 $被认为是狄拉克半学或拓扑绝缘子的潜在候选者，与拓扑相变紧密。与密度功能理论计算相反，最近的光电性结果促使了具有圆锥形色散的两波段模型。在这里，我们通过使用$ \ textbf {k} \ cdot \ textbf {p} $理论得出Zrte $ _5 $的四波段模型来调和两者，并将其参数拟合到Ab-Initio频段结构。带有调整的电子结构的光导率与实验数据的关键特征相匹配。化学势随温度而变化，以至于它可以完全在零和室温之间跨越间隙。温度依赖性电阻率显示了一个较大的峰，并从理论上确认了最近实验的结论，将电阻率峰的起源归因于化学电位与温度的大变化。
ZrTe$_5$ is considered a potential candidate for either a Dirac semimetal or a topological insulator in close proximity to a topological phase transition. Recent optical conductivity results motivated a two-band model with a conical dispersion in 2D, in contrast to density functional theory calculations. Here, we reconcile the two by deriving a four-band model for ZrTe$_5$ using $\textbf{k} \cdot \textbf{p}$ theory, and fitting its parameters to the ab-initio band structure. The optical conductivity with an adjusted electronic structure matches the key features of experimental data. The chemical potential varies strongly with temperature, to the point that it may cross the gap entirely between zero and room temperature. The temperature-dependent resistivity displays a broad peak, and confirms theoretically the conclusions of recent experiments attributing the origin of the resistivity peak to the large shift of the chemical potential with temperature.
