Controllable nucleation and deformation of skyrmions on surface of magnetic nanotubular monolayer

Magnetic skyrmions emerge when the energy of ferromagnetic exchange interaction promoting parallel alignment of spins enters in competition with energies favoring non-collinear alignment of spins such as Dzyaloshinskii–Moriya interaction (DMI), long-rang dipole–dipole interaction (DDI), or higher-order exchange interactions. We perform an unbiased Monte Carlo simulation to study the DMI-based skyrmion nucleation and stabilization on the surface of magnetic nanotubular monolayer controlled by tuning constants of DDI (g) and next-nearest-neighbor antiferromagnetic exchange interaction (j’) with appropriate balance. Without g and j’, the loosely distributed skyrmions initially nucleate on the surface of nanotube approaching to the magnetic field (h) direction with increasing h in the intermediate range. Then, the skyrmion size, shape, density, distribution and crystal structure, as well as its driven field range, are tailored by g and j’. This work demonstrates the skyrmion nucleation mechanisms in three-dimensional magnetic nanostructures with curvature effect and multiple interactions, serving as a benchmark for a guide to experimentalists for preparation of samples in magnetic skyrmion states.