Alter-magnetic properties in the Pnma space group

Abstract To discover potential altermagnetic materials and decipher their intrinsic properties, we performed high-throughput computational screening on the Materials Project database, with a specific focus on antiferromagnetic compounds belonging to the Pnma space group. This screening identified 140 candidate materials, and further analysis revealed that 91 of these candidates preferentially stabilize in altermagnetic ground states. Taking MnTeO 3 as a prototypical example, we carried out comprehensive first-principles calculations ( GGA+U) and systematic symmetry analysis to explore its electronic structure, magnetic ordering, and orbital configurations. Our results confirm that MnTeO 3 exhibits a G -type antiferromagnetic ( G -AFM) ground state, accompanied by G -type orbital ordering. Notably, the unique symmetry protection inherent to MnTeO 3 ’s G -AFM phase gives rise to distinct altermagnetic responses, including: (i) prominent anomalous transport effects, such as anomalous Hall conductivity (AHC), anomalous Nernst conductivity (ANC), and thermal anomalous Hall conductivity (TAHC); and (ii) strong magneto-optical responses, manifested through pronounced Kerr and Faraday effects.