Random dynamics of plane polynomial automorphisms

Let $\mu$ be a finitely supported probability measure on the group of automorphisms of ${\mathbb{A}}_{\mathbb{C}}^2$. If the group generated by the support of $\mu$ is non-elementary and contains only loxodromic elements, we show the existence of dynamical Green functions associated to random products. We derive consequences for $\mu$-stationary measures: they are compactly supported, and we can apply Roda’s theorem to show stiffness when the action is non-dissipative.