Interlayer Dzyaloshinskii–Moriya interaction tuned magnetic ground states in rectangular spin-lattice heterojunctions

Magnetic heterostructures, owing to their intricate spin interactions, provide a versatile platform for exploring emergent spin configurations and tunable magnetic phenomena. In this work, we investigate the regulatory role of interlayer interactions on magnetic order using a heterojunction model composed of an AB-stacked rectangular spin-lattice system. Monte Carlo simulations based on an effective spin Hamiltonian, including the Heisenberg exchange interaction, Dzyaloshinskii–Moriya interaction (DMI), and magnetocrystalline anisotropy, reveal that interlayer DMI can induce controllable magnetic stripe-domain walls or skyrmion states. Increasing the x or y component of interlayer DMI (Dx or Dy) drives the system from a ferromagnetic phase to transverse or longitudinal stripe-domain phases with controllable size. To validate this model, we designed a two-dimensional material CrSBrI through iodine substitution in two-dimensional ferromagnetic CrSBr. First-principles calculations combined with Monte Carlo simulations confirm the presence of interlayer DMI and the emergence of stripe-domain states. Strain engineering further enables efficient tuning of domain-wall properties, thereby modulating electron, spin, magnon, and heat transport.