Quantum critical points separating weak ferromagnetic and paramagnetic phases trigger many novel phenomena. Dynamical spin fluctuations not only suppress the long-range order, but can also lead to unusual transport and even superconductivity. Combining quantum criticality with topological electronic properties presents a rare and unique opportunity. Here, by means of ab initio calculations and magnetic, thermal, and transport measurements, we show that the orthorhombic CoTe2 is close to ferromagnetism, which appears suppressed by spin fluctuations. Calculations and transport measurements reveal nodal Dirac lines, making it a rare combination of proximity to quantum criticality and Dirac topology.
@article{arxiv.2208.13334,
title = {CoTe2: A quantum critical Dirac metal with strong spin fluctuations},
author = {Peter E. Siegfried and Hari Bhandari and Jeanie Qi and Rojila Ghimire and Jayadeep Joshi and Zachary T. Messegee and Willie Beeson and Kai Liu and Madhav Prasad Ghimire and Yanliu Dang and Huairuo Zhang and Albert Davydov and Xiaoyan Tan and Patrick M. Vora and Igor I. Mazin and Nirmal J. Ghimire},
journal= {arXiv preprint arXiv:2208.13334},
year = {2022}
}