Magnetic skyrmions: topologically protected spin textures with Q = ±1
Magnetic skyrmions are topologically protected spin textures characterized by integer topological charge Q = (1/4π)∫n·(∂ₓn × ∂ᵧn)dA = ±1. The Dzyaloshinskii–Moriya (DM) interaction in non-centrosymmetric magnets stabilizes skyrmion lattices. Their topological charge makes them robust against smooth deformations — annihilation requires overcoming a finite energy barrier.