Power-law distribution of avalanche sizes in the field-driven transformation of a phase-separated oxide

Abstract

At low temperature $(T\sim 1.5\mathrm{K})$, the isothermal magnetization curves of a phase-separated manganese oxide $\left({\mathrm{Pr}}_{0.6}{\mathrm{Ca}}_{0.4}{\mathrm{Mn}}_{0.96}{\mathrm{Ga}}_{0.04}{\mathrm{O}}_3\right)$ are found to exhibit a large number of small steps. Analysis of this phenomenon shows several features which are typical of avalanchelike dynamics. These findings lend further support to the martensitic origin of the magnetization steps encountered in phase-separated manganites.