2026/07/30 by Shantanu Pathak, Saswata Bhattacharya
Physics and Astronomy · #cond-mat.mtrl-sci
arxiv created 2026/07/30 · arxiv updated 2026/07/31
Altermagnets combine collinear antiferromagnetic order with nonrelativistic spin splitting, enabling spintronic functionalities without relying on spin--orbit coupling. While staggered orbital ordering has recently emerged as an alternative route to altermagnetism, its generality has remained unexplored. Here, we establish a universal crystal-field design principle for orbital-order-driven altermagnetism. We show that structural relaxation consistently reconstructs the crystal-field landscape, activating a common dxz/dyz orbital manifold that drives spontaneous staggered orbital ordering and robust d-wave nonrelativistic spin splitting across transition-metal compounds spanning electron fillings from d1 to d7. By introducing a unified symmetry framework based on layer-dependent magnetic and orbital order parameters, we demonstrate how interlayer stacking determines whether the system realizes a bulk altermagnetic state or a globally compensated antialtermagnetic phase. Furthermore, we reveal that this symmetry-protected spin-split texture gives rise to highly anisotropic spin-polarized conductivities. Our results establish crystal-field engineering as a predictive design strategy for discovering and engineering orbital-order-driven altermagnets.