Ryu Hyejin, Park Se Young, Li Lijun, Ren Weijun, Neaton Jeffrey B, Petrovic Cedomir, Hwang Choongyu, Mo Sung-Kwan
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
Max Planck POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang, 37673, Korea.
Sci Rep. 2018 Oct 17;8(1):15322. doi: 10.1038/s41598-018-33512-w.
We investigate the electronic structure of BaMnBi and BaZnBi using angle-resolved photoemission spectroscopy and first-principles calculations. Although they share similar structural properties, we show that their electronic structure exhibit dramatic differences. A strong anisotropic Dirac dispersion is revealed in BaMnBi with a decreased asymmetry factor compared with other members of AMnBi (A = alkali earth or rare earth elements) family. In addition to the Dirac cones, multiple bands crossing the Fermi energy give rise to a complex Fermi surface topology for BaZnBi. We further show that the strength of hybridization between Bi-p and Mn-d/Zn-s states is the main driver of the differences in electronic structure for these two related compounds.
我们使用角分辨光电子能谱和第一性原理计算研究了BaMnBi和BaZnBi的电子结构。尽管它们具有相似的结构性质，但我们发现它们的电子结构存在显著差异。在BaMnBi中揭示了强烈的各向异性狄拉克色散，与AMnBi（A =碱土或稀土元素）家族的其他成员相比，其不对称因子减小。除了狄拉克锥之外，多个穿过费米能级的能带导致了BaZnBi复杂的费米面拓扑结构。我们进一步表明，Bi-p与Mn-d/Zn-s态之间的杂化强度是这两种相关化合物电子结构差异的主要驱动因素。
