Type-II Weyl nodes, flat bands, and evidence for a topological Hall-effect in the new ferromagnet FeCr${}_3$Te${}_6$

Abstract

The interplay between linearly dispersing or Dirac-like, and flat electronic bands, for instance, in the kagome ferromagnets, has attracted attention due to a possible interplay between topology and electronic correlations. Here, we report the synthesis, structural, electrical, and magnetic properties of a single-crystalline ferromagnetic compound, namely Fe${}_{1/3}$CrTe${}_2$ or FeCr${}_3$Te${}_6$, which crystallizes in the $P\bar{3}m1$ space group instead of the $I2/m$ previously reported for FeCr${}_2$Te${}_4$. Electronic band structure calculations reveal type-II Dirac nodes and relatively flat bands near the Fermi level (${\epsilon }_F$). This compound shows onset Curie temperature $T_{\text{c}}\simeq 120$ K, followed by an additional ferromagnetic transition near $T_{\text{c2}}\sim 92.5$ K. Below $T_{\text{c}}$, FeCr${}_3$Te${}_6$ displays a pronounced anomalous Hall effect, as well as sizable coercive fields that exceed ${\mu }_{0}H=1$~T at low $T$s. However, a scaling analysis indicates that the anomalous Hall effect results from a significant intrinsic contribution, as expected from the calculations, but also from the extrinsic mechanism, i.e., scattering. The extrinsic contribution probably results from occupational disorder at the 1b Fe-site within the van der Waals gap of the CrTe${}_2$ host. We also observe evidence for a topological Hall component superimposed onto the overall Hall response, suggesting the presence of chiral spin textures akin to skyrmions in this centrosymmetric system. Their possible presence will require experimental confirmation.

arXiv comment8 pages, 7 figures

References in corpus (24)

• Anomalous Hall effect
• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• A linear response approach to the calculation of the effective interaction parameters in the LDA+U method
• Type-II Weyl Semimetals
• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Topological Materials: Weyl Semimetals
• Massive Dirac fermions in a ferromagnetic kagome metal
• Anomalous Hall effect in ferromagnetic semiconductors
• Proper Scaling of the Anomalous Hall Effect
• Progress and prospects in magnetic topological materials
• Negative flat band magnetism in a spin-orbit coupled correlated kagome magnet
• Topological flat bands in frustrated kagome lattice CoSn
• Observation of Magnetic Skyrmion Bubbles in a van der Waals ferromagnet Fe3GeTe2
• Room temperature 2D ferromagnetism in few-layered 1$T$-CrTe${}_2$
• Quantized Anomalous Hall Effect in Two-Dimensional Ferromagnets - Quantum Hall Effect from Metal -
• Néel-type skyrmions and their current-induced motion in van der Waals ferromagnet-based heterostructures
• Room-temperature sub-100 nm Néel-type skyrmions in non-stoichiometric van der Waals ferromagnet $\mathrm{F}{\mathrm{e}}_{3-\mathrm{x}}\mathrm{GaT}{\mathrm{e}}_2$ with ultrafast laser writability
• Tailoring Magnetism in Self-intercalated Cr1+δTe2 Epitaxial Films
• FeCr${}_2$S${}_4$ in magnetic fields: possible evidence for a multiferroic ground state
• Structural, electronic, and magnetic properties of CrTe2
• Broken inversion symmetry in van der Waals topological ferromagnetic metal iron germanium telluride
• Three-dimensional Ising Ferrimagnetism of Cr-Fe-Cr trimers in FeCr2Te4
• Anomalous Hall effect in weak-itinerant ferrimagnet FeCr${}_2$Te${}_4$
• Absence of structural transition in TM0.5IrTe2 (TM=Mn, Fe, Co, Ni)