Abstract. The Bethe strip of width m is the Cartesian product B f1; : : : ; mg, where B is the Bethe lattice (Cayley tree). We consider Anderson-like Hamiltonians H D 1 2 ˝1 C 1˝A C V on a Bethe strip with connectivity K 2, where A is an m m symmetric matrix, V is a random matrix potential, and is the disorder parameter. Under certain conditions on A and K, for which we previously proved the existence of absolutely continuous spectrum for small , we now obtain ballistic behavior for the spreading of wave packets evolving under H for small .
Mathematics Subject Classification (2010). Primary 82B44; Secondary 47B80, 60H25.