Conventional antiferromagnets (AFMs) preserve time-reversal symmetry (TRS). Recently, altermagnets (AMs) which break TRS and show momentum-dependent spin splitting have been proposed. The occurrence of AMs depends on a special geometry around the magnetic ion. Here, we show that AMs can be induced in a general lattice by leveraging the coupling between the charge and spin degrees of freedom. We study numerically the quantum phases in bimetallic systems by modeling them using an interpenetrated bipartite square lattice. Our mean-field theory calculations of this model's band structures reveal that charge order and antiferromagnetic spin order in different sublattices lead to altermagnetism. The origin of AM phase is further shown analytically to stem from a unitary transformation of the Hamiltonian matrix between the up spin at $(k_x,k_y)$ and down spin at $(k_x,-k_y)$ when the $A$ sublattice is charge ordered. The proposed model is then validated by comparing the band structures of pristine ${\mathrm{LaMnO}}_3$ and doped ${\mathrm{La}}_{1-x}{\mathrm{Sr}}_x{\mathrm{MnO}}_3 (x=0.5)$ (LSMO) using density functional theory. This suggests a tunable approach to achieving altermagnetism in bimetallic systems, broadening the range of such materials.

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• Altermagnetism
• Magnetic order
• Altermagnets
• Magnetic systems
• Density functional calculations
• Extended Hubbard model
• Lattice models in condensed matter
• Mean field theory