Anomalous Hall Effect in Topological Weyl and Nodal-Line Semimetal Heusler Compound Co2VAl

Magnetic topological semimetals (TSMs) with broken time-reversal symmetry are very rare and have drawn significant attention in condensed matter physics due to their numerous intriguing topological properties. Among these various magnetic TSMs, Co-2-based full Heusler compounds are of current interest, since a few of these materials exhibit Weyl and nodal fermions in their topological band structure. In this work, we report a comprehensive study of anomalous Hall effect (AHE) in the ferromagnetic full Heusler compound Co-2 VAI. Recent studies indicate that the intrinsic AHE is closely related to the Berry curvature of the occupied electronic Bloch states. The present study of Co-2 VA1 attempts to understand and explore the possibility of topology-induced AHE. The anomalous Hall resistivity rho(A)(xy) is observed to scale quadratically with the longitudinal resistivity rho(xx). Our experimental results also reveal that the anomalous Hall conductivity (AHC) is similar to 85 cm(-1) at 2 K with an intrinsic contribution of similar to 75.6 S cm(-1), and is nearly insensitive to temperature. The first principle calculations note that the Berry curvature originated from a gapped nodal line and symmetry-protected Weyl nodes near the Fermi level (E-F) is the main source of AHE in this compound. Thus, this investigation on Co-2 VAI discloses that it is a ferromagnetic Weyl and nodal-line TSM. The theoretically calculated AHC is in well agreement with the experimentally obtained AHC.