Unusual Electronic Structure of Dirac Material BaMnSb$_2$ Revealed by Angle-Resolved Photoemission Spectroscopy

TL;DR

This study uses high-resolution photoemission and calculations to reveal that BaMnSb$_2$ has an unusual, nearly linear electronic structure with a distinctive Fermi surface, deviating from theoretical predictions.

Contribution

The paper provides the first detailed experimental characterization of BaMnSb$_2$'s electronic structure, highlighting its unusual linear bands and Fermi surface features.

Findings

Bands are nearly linear over a wide energy range

Fermi surface includes a hole pocket at Γ and a spot at Y

Electronic structure deviates from theoretical calculations

Abstract

High resolution angle resolved photoemission measurements and band structure calculations are carried out to study the electronic structure of BaMnSb$_2$. All the observed bands are nearly linear that extend to a wide energy range. The measured Fermi surface mainly consists of one hole pocket around $\Gamma$ and a strong spot at Y which are formed from the crossing points of the linear bands. The measured electronic structure of BaMnSb$_2$ is unusual and deviates strongly from the band structure calculations. These results will stimulate further efforts to theoretically understand the electronic structure of BaMnSb$_2$ and search for novel properties in this Dirac material.