Large anomalous Hall effect and unusual domain switching in an orthorhombic antiferromagnetic material NbMnP

Abstract

Specific antiferromagnetic (AF) spin configurations generate large anomalous Hall effects (AHEs) even at zero magnetic field through nonvanishing Berry curvature in momentum space. In addition to restrictions on AF structures, suitable control of AF domains is essential to observe this effect without cancellations among its domains; therefore, compatible materials remain limited. Here we show that an orthorhombic noncollinear AF material, NbMnP, acquired AF structure-based AHE and controllability of the AF domains. Theoretical calculations indicated that a large Hall conductivity of ~230 Ω−1cm−1 originated from the AF structure of NbMnP. Symmetry considerations explained the production of a small net magnetization, whose anisotropy enabled the generation and cancellation of the Hall responses using magnetic fields in different directions. Finally, asymmetric hysteresis in NbMnP shows potential for the development of controllability of responses in AF materials.

Altermagnetism with non-collinear spins

“…state 27 of Gd 2 CuO 4 , the magnetic state of each layer of La 2 CuO 4 5 or Sr 2 IrO 4 35 , and the magnetic state of NbMnP 36 . Type-II altermagnets do not have non-zero net magnetic moment nor exhibit ferromagnet-like behaviors but still have broken PT symmetry.…”