Single helicity of the triple- q triangular skyrmion lattice state in the cubic chiral helimagnet EuPtSi

The magnetic skyrmion lattice is a crystallization of spin-swirling particle-like objects composed of multiple helimagnetic modulation waves with the same helicity (sense of rotation). Despite the widespread observation of this spectacular structure, the experimental verification of the unified helicity has not yet been achieved. Using circularly polarized resonant x-ray diffraction, the authors study here the triangular skyrmion lattice in the chiral helimagnet EuPtSi and demonstrate that the helicity is indeed unified. This method has great potential for unraveling the chiral structures of emergent magnetic phases.