Spectral line

Quantum mechanics

Ground state

Perpendicular

Topological quantum number

Ferromagnetism

Skyrmion

Curvilinear coordinates

Excitation

Acoustics

Lattice (music)

Physics

Mathematics

Condensed matter physics

Geometry

Combinatorics

Topology (electrical circuits)

Multiplet

Physical Review Letters

Typically, the chiral magnetic Skyrmion is a single-state excitation. Here we propose a system, where multiplet of Skyrmion states appears and one of these states can be the ground one. We show that the presence of a localized curvilinear defect drastically changes the magnetic properties of a thin perpendicularly magnetized ferromagnetic film. For a large enough defect amplitude a discrete set of equilibrium magnetization states appears forming a ladder of energy levels. Each equilibrium state has either a zero or a unit topological charge; i.e., topologically trivial and Skyrmion multiplets generally appear. Transitions between the levels with the same topological charge are allowed and can be utilized to encode and switch a bit of information. There is a wide range of geometrical and material parameters, where the Skyrmion level has the lowest energy. Thus, periodically arranged curvilinear defects can result in a Skyrmion lattice as the ground state.

Multiplet of Skyrmion States on a Curvilinear Defect: Reconfigurable Skyrmion Lattices