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Anisotropic Dirac Fermions in BaMnBi2 and BaZnBi2.

ABSTRACT: We investigate the electronic structure of BaMnBi2 and BaZnBi2 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 BaMnBi2 with a decreased asymmetry factor compared with other members of AMnBi2 (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 BaZnBi2. 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.

SUBMITTER: Ryu H

PROVIDER: S-EPMC6192995 | biostudies-other | 2018 Oct

REPOSITORIES: biostudies-other

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Anisotropic Dirac Fermions in BaMnBi2 and BaZnBi2.

Ryu Hyejin H Park Se Young SY Li Lijun L Ren Weijun W Neaton Jeffrey B JB Petrovic Cedomir C Hwang Choongyu C Mo Sung-Kwan SK

Scientific reports 20181017 1

We investigate the electronic structure of BaMnBi2 and BaZnBi2 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 BaMnBi2 with a decreased asymmetry factor compared with other members of AMnBi2 (A = alkali earth or rare earth elements) family. In add ...[more]

PMID: 30333501

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