Electronic structure in a rare-earth based nodal-line semimetal candidate PrSbTe

TL;DR

This study investigates the electronic structure of PrSbTe, a rare-earth nodal-line semimetal candidate, revealing Dirac crossings and nodal lines through ARPES and computations, highlighting the role of spin-orbit coupling.

Contribution

It provides the first detailed experimental and theoretical analysis of PrSbTe's topological electronic structure, emphasizing the impact of spin-orbit coupling in RESbTe materials.

Findings

Presence of gapless Dirac crossings along XR direction

Identification of a diamond-shaped nodal plane at the Brillouin zone center

No phase transition observed down to 2 K

Abstract

Nodal line semimetals feature topologically protected band crossings between the bulk valence and conduction bands that extend along a finite dimension in the form of a line or a loop. While ZrSiS and similar materials have attracted extensive research as hosts for the nodal line semimetallic phase, an alternative avenue has emerged in the form of isostructural rare-earth (RE) based RESbTe materials. Such systems possess intriguing potentialities for harboring elements of magnetic ordering and electronic correlations owing to the presence of 4f electrons intrinsic to the RE elements. In this study, we have carried out angle resolved photoemission spectroscopy (ARPES) and thermodynamic measurements in conjunction with first principles computations on PrSbTe to elucidate its electronic structure and topological characteristics. Magnetic and thermal characterizations indicate the presence of well-localized 4f states with the absence of any discernible phase transition down to 2 K. The ARPES results reveal the presence of gapless Dirac crossings that correspond to a nodal-line along the XR direction in the three-dimensional Brillouin zone. Furthermore, Dirac crossing that makes up nodal line, which forms a diamond-shaped nodal plane centered at the center of the Brillouin zone is also identified within the experimental resolution. This study on the electronic structure of PrSbTe contributes to the understanding of the pivotal role played by spin-orbit coupling in the context of the RESbTe family of materials