Unraveling the solitonic nature of spin-stripes to skyrmion transition in a Fe/Gd thin film.*

Understanding phase-transition of one-dimensional spin-stripes to two-dimensional skyrmions in magnetic thin films exhibiting enigmatic display of soliton physics, is essential for the development of both fundamental and applied sciences. Unlike in antisymmetric Dzylozhinskii-Moriya interaction (DMI) materials of fixed chirality, the field evolution of stripe-structures in dipolar interaction mediated thin-films has remained unresolved and is a topic of great potential for future research. Herein we observe using X-ray resonant scattering that stripes in a dipolar interaction dominant Fe/Gd film behave like finite-sized chiral soliton lattice (CSL) exhibiting discrete jumps in periodicity with applied field. Our results also show absence of discrete jumps after CSL-to-skyrmion transition thus providing insights into the the role of chirality and dimensionality in different topological magnetic structures.