Temperature‐induced changes of domain structures in ultrathin magnetic films

Abstract

We describe the thermal-driven evolution of stripe domain structures in ultrathin magnetic films with perpendicular anisotropy. Taking into account temperature dependencies of the film magnetic parameters we analyze possible temperature dependencies of the domain period. It is shown that the film heating leads to a decrease in the domain period. In soft films thermally assisted domain nucleation could provide a continuous decrease of the domain period while the domain structure passes through equilibrium states. On increasing the temperature of a hard film, the domain structure exists as metastable one adjusting its period by a sequence of jumps towards to equilibrium.

Transformation of magnetic structure in amorphous microwires induced by temperature and high frequency magnetic field

“…The actual pathway from a metastable state to an equilibrium state depends upon intrinsic and external agitations, which can include the rate of the temperature changes, thermal activation of domain wall displacements and an application of magnetic fields. Depending upon these factors, various scenarios of the temperature evolution of the domain structure can take place: (i) a jump-like DS transition can occur in the domain size and period that corresponds to a higher (or lower) temperature [29]; (ii) continuous changes of the domain geometry and size occur when the DS slowly passes through the chain of equilibrium states [31]; finally, (iii) the coexistence of two domain structures can exist characterized by different domain shapes, sizes and periods [28]. In general, the main magnetic parameters that determine the equilibrium domain size and period are the domain wall width d = (A/K) 1/2 and the characteristic length l c = r/4pM S 2 , where r = 4(AK) 1/2 is the domain wall energy surface density and A is the exchange constant.…”