Mechanical control of magnetic exchange and response in GdRu2Si2

Magnetic skyrmions are nanoscale topological spin textures promising for low-power spintronics, provided their stability can be controlled. Mechanical strain modifies interatomic distances and underlying magnetic interactions, offering an efficient control route. We present a computational study on the effect of uniaxial strain in GdRu 2 Si 2 , a centrosymmetric material hosting a field-induced skyrmion lattice without Dzyaloshinskii-Moriya interactions. Using first-principles density functional theory, we demonstrate the pronounced sensitivity of exchange and anisotropy to structural distortions. These interactions are integrated into a classical spin model with macroscopic dipolar interactions to construct magnetic phase diagrams under compressive and tensile strain. Dipolar fields successfully reproduce the multiple- Q⃗ Q ⃗ zero-field ground state. Crucially, while higher-order multi-spin interactions are required to lock in the exact internal symmetries of field-induced textures, compressive strain ( ~ 2%) substantially expands the stability region of the Q⃗₁₀₀ Q ⃗ 100 -driven topologically nontrivial phases. This results from shifted critical fields and an enhanced energy scale of the favored magnetic wave vector. Conversely, tensile strain promotes a different ordering vector, Q⃗₁₁₀ Q ⃗ 110 , leading to entirely distinct phase behavior. This work quantitatively explains the structural-magnetic coupling in GdRu 2 Si 2 and establishes strain engineering as a powerful approach to control non-trivial magnetic phases in centrosymmetric magnets.