Evidence of non-trivial Berry phase and Kondo physics in SmBi

TL;DR

This study reveals non-trivial Berry phase and Kondo physics in SmBi, a correlated topological semimetal, through bulk measurements showing quantum oscillations, magnetic transitions, and topological Fermi surface features.

Contribution

It provides the first evidence of non-trivial Berry phase and Kondo effects in SmBi, highlighting the interplay of topology, magnetism, and electron correlations in this material.

Findings

Detection of quantum oscillations at low magnetic fields.

Identification of a non-trivial Berry phase in Fermi pockets.

Observation of magnetic transitions at 9 K and 7 K.

Abstract

Realization of semimetals with non-trivial topologies such as Dirac and Weyl semimetals, have provided a boost in the study of these quantum materials. Presence of electron correlation makes the system even more exotic due to enhanced scattering of charge carriers, Kondo screening etc. Here, we studied the electronic properties of single crystalline, SmBi employing varied state of the art bulk measurements. Magnetization data reveals two magnetic transitions; an antiferromagnetic order with a Neel temperature of ~ 9 K and a second magnetic transition at a lower temperature (= 7 K). The electrical resistivity data shows an upturn typical of a Kondo system and the estimated Kondo temperature is found to be close to the Neel temperature. High quality of the crystal enabled us to discover signature of quantum oscillation in the magnetization data even at low magnetic field. Using a Landau level fan diagram analysis, a non-trivial Berry phase is identified for a Fermi pocket revealing the topological character in this material. These results demonstrate an unique example of the Fermiology in the antiferromagnetic state and opens up a new paradigm to explore the Dirac fermion physics in correlated topological metal via interplay of Kondo interaction, topological order and magnetism.