  We study nonequilibrium quantum transport through a mesoscopic wire coupled
via local exchange to a ferromagnetic spin chain. Using the Keldysh formalism
in the self-consistent Born approximation, we identify fingerprints of the
magnetic polaron state formed by hybridization of electronic and magnon states.
Because of its low decoherence rate, we find coherent transport signals. Both
elastic and inelastic peaks of the differential conductance are discussed as a
function of external magnetic fields, the polarization of the leads and the
electronic level spacing of the wire.
