论文标题
朝着温度引起的SNTE中的拓扑相变：第一原理研究
Towards temperature-induced topological phase transition in SnTe: A first principles study
论文作者
论文摘要
使用第一原理方法计算拓扑晶体绝缘子SNTE的散装条带结构的温度重归其化。我们明确地包括热膨胀诱导的电子状态修饰及其带反转对电子 - phonon相互作用的影响。我们表明，随着热膨胀和电子 - phonon相互作用均随着温度的升高，直接间隙随温度的降低而降低。当材料接近相变时，由于电子 - 光子相互作用而引起的带隙重新归一化表现出非线性依赖性，而在带边缘附近的传导带状态的寿命显示出具有温度的非单调行为。这些效应应对SNTE和其他拓扑绝缘子中的散装电子和热电传输具有重要意义。
The temperature renormalization of the bulk band structure of a topological crystalline insulator, SnTe, is calculated using first principles methods. We explicitly include the effect of thermal-expansion-induced modification of electronic states and their band inversion on electron-phonon interaction. We show that the direct gap decreases with temperature, as both thermal expansion and electron-phonon interaction drive SnTe towards the phase transition to a topologically trivial phase as temperature increases. The band gap renormalization due to electron-phonon interaction exhibits a non-linear dependence on temperature as the material approaches the phase transition, while the lifetimes of the conduction band states near the band edge show a non-monotonic behavior with temperature. These effects should have important implications on bulk electronic and thermoelectric transport in SnTe and other topological insulators.
