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CoTe2 : A Quantum Critical Dirac Metal with Strong Spin Fluctuations.
Peter E Siegfried1,2, Hari Bhandari1,2, Jeanie Qi3
1Department of Physics and Astronomy, George Mason University, Fairfax, VA, 22030, USA.
Advanced Materials (Deerfield Beach, Fla.)
|April 3, 2023
Summary
Orthorhombic CoTe2 is near quantum criticality, with spin fluctuations suppressing ferromagnetism. This material exhibits nodal Dirac lines, merging quantum criticality with topological electronic properties for novel phenomena.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Quantum critical points drive novel phenomena like unusual transport and superconductivity.
- Dynamical spin fluctuations near quantum criticality can suppress long-range magnetic order.
- Combining quantum criticality with topological electronic properties offers unique research opportunities.
Purpose of the Study:
- Investigate the electronic and magnetic properties of orthorhombic CoTe2.
- Explore the interplay between quantum criticality and topological electronic states.
- Determine if CoTe2 exhibits a combination of proximity to ferromagnetism and topological properties.
Main Methods:
- Ab initio calculations to model electronic structure.
- Experimental measurements including magnetic, thermal, and transport properties.
- Analysis of spin fluctuations and their effect on magnetic order.
Main Results:
- Orthorhombic CoTe2 is found to be close to a ferromagnetic quantum critical point.
- Spin fluctuations are observed to suppress long-range ferromagnetic order.
- Calculations and transport measurements reveal the presence of nodal Dirac lines, indicating non-trivial topology.
Conclusions:
- Orthorhombic CoTe2 represents a rare material combining proximity to quantum criticality with Dirac topology.
- The findings open avenues for exploring novel quantum phenomena arising from this unique combination.
- This study highlights CoTe2 as a promising platform for next-generation electronic devices.
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