Electron transport in a finite one dimensional quantum spin chain (with
ferromagnetic exchange) is studied within an s−d exchange Hamiltonian. Spin
transfer coefficients strongly depend on the sign of the s−d exchange
constant. For a ferromagnetic coupling, they exhibit a novel resonant pattern,
reflecting the salient features of the combined electron-spin system. Spin-flip
processes are inelastic and feasible at finite voltage or at finite
temperature.Comment: 4 pages including 4 .eps figure