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arXiv · 2208.13334

CoTe2: A quantum critical Dirac metal with strong spin fluctuations

Peter E. Siegfried·Hari Bhandari·Jeanie Qi·Rojila Ghimire·Jayadeep Joshi·Zachary T. Messegee·Willie Beeson·Kai Liu·Madhav Prasad Ghimire·Yanliu Dang·Huairuo Zhang·Albert Davydov·Xiaoyan Tan·Patrick M. Vora·Igor I. Mazin·Nirmal J. Ghimire
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Abstract

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 CoTe$_2$ 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.

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Peter E. Siegfried, Hari Bhandari, Jeanie Qi, Rojila Ghimire, Jayadeep Joshi, Zachary T. Messegee, Willie Beeson, Kai Liu, Madhav Prasad Ghimire, Yanliu Dang, Huairuo Zhang, Albert Davydov, Xiaoyan Tan, Patrick M. Vora, Igor I. Mazin, Nirmal J. Ghimire. 2022-08-29. CoTe2: A quantum critical Dirac metal with strong spin fluctuations. https://arxiv.org/abs/2208.13334

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