论文标题
观察拓扑狄拉克 - 敏捷候选库uas中倒带结构的观察
Observation of inverted band structure in topological Dirac-semimetal candidate CaAuAs
论文作者
论文摘要
我们已经进行了三ic虫caauas的高分辨率角度分辨光发射光谱法，该光谱被预测为三维拓扑迪拉克半学（TDS）。通过准确确定散装式结构，我们揭示了具有主孔载体的三维和准二维费米表面的共存。布里渊区中心周围的带状结构的特征是孔和电子口袋之间的能量重叠，与第一原理的带结构计算非常吻合。这表明出现散装波段倒置，支持CAAUAS中的TDS状态。由于除TDS性质外，化学组成的可调性很高，因此CAAUAS为研究了从TDS到其他外来拓扑阶段的量子相过渡提供了宝贵的机会。
We have performed high-resolution angle-resolved photoemission spectroscopy of ternary pnictide CaAuAs which is predicted to be a three-dimensional topological Dirac semimetal (TDS). By accurately determining the bulk-band structure, we have revealed the coexistence of three-dimensional and quasi-two-dimensional Fermi surfaces with dominant hole carriers. The band structure around the Brillouin-zone center is characterized by an energy overlap between hole and electron pockets, in excellent agreement with first-principles band-structure calculations. This indicates the occurrence of bulk-band inversion, supporting the TDS state in CaAuAs. Because of the high tunability in the chemical composition besides the TDS nature, CaAuAs provides a precious opportunity for investigating the quantum phase transition from TDS to other exotic topological phases.
