Dynamics of the first-order magnetostructural transition in Gd<Subscript>5</Subscript>(Si<Subscript> x </Subscript>Ge<Subscript>1-x </Subscript>)<Subscript>4</Subscript>

The dynamics at a mesoscopic scale of the first-order magnetostructural transition in a Gd<Subscript>5</Subscript>(Si<Subscript> x </Subscript>Ge<Subscript>1-x </Subscript>)<Subscript>4</Subscript> alloy with x=0.05 is studied. We examine the effect of inducing the transition either by T or H on the entropy change. In addition, we analyse the avalanches between metastable states during the transition. The athermal character of the transition is evidenced. It is also shown that cycling through the transition leads to a reproducible pattern with no characteristic size of the avalanches. Copyright Springer-Verlag Berlin/Heidelberg 2004