Electronic Structure Studies of Detwinned BaFe$_2$As$_2$ by Photoemission

TL;DR

This study uses ARPES to investigate the electronic structure of detwinned BaFe2As2, revealing band dispersions, Fermi surface shapes, and Dirac cones consistent with theoretical predictions, enhancing understanding of its orbital order and magnetic properties.

Contribution

First ARPES study on mechanically detwinned BaFe2As2 revealing detailed band structures and Fermi surface topology consistent with orbital ordered states.

Findings

Fermi surface shapes match orbital order predictions

Dirac-cone like dispersions identified near the Γ-point

Band dispersions agree with calculations assuming 0.2 μB magnetic moment

Abstract

We performed angle resolved photoelectron spectroscopy (ARPES) studies on mechanically detwinned BaFe2As2. We observe clear band dispersions and the shapes and characters of the Fermi surfaces are identified. Shapes of the two hole pockets around the {\Gamma}-point are found to be consistent with the Fermi surface topology predicted in the orbital ordered states. Dirac-cone like band dispersions near the {\Gamma}-point are clearly identified as theoretically predicted. At the X-point, split bands remain intact in spite of detwinning, barring twinning origin of the bands. The observed band dispersions are compared with calculated band structures. With a magnetic moment of 0.2 ?B per iron atom, there is a good agreement between the calculation and experiment.