Nonsymmorphic symmetry enforced Weyl nodal metal in chalcopyrite MnGeAs2.

Band degeneracy-driven topological phases in condensed matter physics have paved the way for a distinct type of Weyl systems. Ongoing research delves into quasi-particles beyond Dirac and Weyl semimetals, investigating their interactions and necessitating the discovery of new quantum materials. Furthermore, the coexistence of Type-I and II Weyl crossings in magnetic Weyl systems, protected by nonsymmorphic crystalline symmetry, represents a rare and intriguing combination. Our study focuses on the experimentally synthesized non-centrosymmetric chalcopyrite MnGeAs2, characterized by broken time-reversal symmetry. Notably, the Type-I and -II gapless Weyl nodal line co-occur in this material, and they exhibit resilience against the strong spin-orbit coupling (SOC) protected by the nonsymmorphic d-glide mirror symmetry. Moreover, the calculated Berry curvature-driven anomalous Hall conductivity (AHC) attains a substantial value of approximately 300 S/cm near the Type-I Weyl nodal line at 26 meV below the E[Formula: see text]. Further, the AHC gets enhanced to 350 S/cm for the mimicked thin film variant of the MnGeAs[Formula: see text]. This study provides insights into the relatively less-explored Weyl nodal line semimetals robust against the strong SOC.