Control of magnetism at the microscopic level with magnetic fields

Information storage and manipulation technologies rely on the formation and control of nanoscopic magnetic domains. Key limitations on information density include thermal fluctuations of small magnetic domains and large thermal loads produced by currents necessary to manipulate them. In contrast, magnetic systems displaying topologically nontrivial magnetic structures have been shown to be robust against thermal fluctuations and can be manipulated with small currents. Here we use Lorentz transmission electron microscopy and small-angle neutron scattering measurements to demonstrate control over the domain topology of an anisotropic hexagonal chiral magnet Mn_1/3NbS₂. Magnetic solitons, twists of magnetization along a single direction, are observed to controllably form either soliton/soliton or soliton/antisoliton pairs which translate and annihilate when exposed to small magnetic fields.