Professor Thorsten Hesjedal FInstP

Abstract:

We identify a three-dimensional skyrmion sideface state in chiral magnets that consists of a thin layer of modulated surface spirals and an array of phase-locked skyrmion screws. Such chiral spin structures lead to a characteristic ‘X’-shaped magnetic diffraction pattern in resonant elastic x-ray scattering, reminiscent of Photo 51 of the DNA double helix diffraction. By measuring both thin plates and bulk Cu2OSeO3 crystals in the field-in-plane geometry, we unambiguously identified the modulated skyrmion strings by retrieving their chirality and helix angle. The breaking of the translational symmetry along the sidefaces suppresses the bulk-favored conical state, providing a stabilization mechanism for the skyrmion lattice phase that has been overlooked so far.