Novel magnetotransport properties of topological nodal-line fermions
Topology and electron correlation are two key ingredients in quantum materials producing novel electronic properties and phases yet-to-be-discovered. Of particular interest are topological nodal-line materials that host unique quasiparticles near the one-dimensional band-degeneracy in the momentum space and exhibit unusual transport properties highly sensitive to electromagnetic perturbations. In this talk, I will present unusual magnetotransport properties of nodal-line fermions when they are isolated from topologically trivial electronic states, strongly correlated, or coupled to magnetic moments. Various magnetotransport phenomena will be discussed, including a giant anomalous Hall effect [1], a colossal angular magnetoresistance [2], significantly enhanced weak antilocalization [3], and an electric-field-driven metal-insulator transition [4]. These findings highlight that topological nodal-line materials represent a promising material platform for developing unprecedented functionalities with potential applications in next-generation electronic and spintronic devices.
[1] K. Kim et al. "Large anomalous Hall current induced by topological nodal lines in a ferromagnetic van der Waals semimetal", Nat. Mater. 17, 794 (2018).
[2] J. Seo et al. "Colossal angular magnetoresistance in ferrimagnetic nodal-line semiconductors" Nature 599, 576–581 (2021).
[3] H. Kim et al. "Quantum transport evidence of isolated topological nodal-line fermions", Nature Communications 13, 7188 (2022).
[4] H. Kim et al. unpublished.