Antiferromagnetic weak topological state in Bismuth square-net based nonsymmorphic lattice

TL;DR

This study synthesizes and characterizes NdBiTe, revealing its antiferromagnetic semimetallic nature with weak topological properties, combining experimental measurements and first-principles calculations.

Contribution

It reports the synthesis and comprehensive magnetic, transport, and electronic structure analysis of NdBiTe, demonstrating its weak topological antiferromagnetic semimetallic state.

Findings

Long-range antiferromagnetic order below 4.5 K

Metallic behavior with positive magnetoresistance

Weak topological nature confirmed by simulations

Abstract

The ZrSiS-class of layered materials offer interesting topological and magnetic characteristics suitable for spintronics applications. In this work, we have synthesized a polycrystalline NdBiTe using solid-state reaction technique and have examined the magnetic properties in 2 - 300 K temperature range using temperature and field-dependent magnetization measurements. Our magnetic and specific heat data demonstrates a long-range antiferromagnetic ordering in the material below 4.5 K. Furthermore, our isothermal magnetization data show a signature of spin-reorientation below Neel temperature. The observed nonlinearity in inverse susceptibility vs temperature data, and a hump in specific heat in 5-20 K range, indicate the existence of crystal field splitting in the material. Our transport properties measurements show the metallic behavior with positive magnetoresistance in the temperature range of 2 - 300 K. The observed rise in resistivity as function of temperature below Neel temperature infers the strongly correlated fermions, which is consistent with the observed large Sommerfeld coefficient. Consistent with experimental results, our first-principles calculations predict an antiferromagnetic semimetallic nature of NdBiTe. Further, our spin-orbit coupled simulations of electronic structure show a signature of weak topological nature of the material.