Electrically controlled Néel vector switching in altermagnets via sublattice Rashba engineering

Altermagnets exhibit spin-split bands without net magnetization, making them attractive for spintronics. However, in most conventional altermagnets, local inversion symmetry of sublattice hinders the intrinsic electrical switching. In this work, we propose a design strategy to realize a distinct class of altermagnets: by deliberately breaking sublattice inversion symmetry, staggered Rashba-type spin-orbit fields with opposite signs emerge, producing asymmetric local torques that enable deterministic, field-free switching of the N\'eel vector. The resulting class of altermagnets features noncentrosymmetric sublattices connected by improper rotations, preserving the hallmark altermagnetic spin-split band structure while unlocking full electrical controllability. Symmetry analysis, tight-binding modeling, and linear response theory confirm this mechanism, establishing a general design principle for electrically controllable altermagnetic spintronics.