We investigate the spin or charge transport in a one-dimensional strongly correlated system by using the adaptive time-dependent density-matrix renormalization-group method. The model we consider is a non-half-filled Hubbard chain with a bond of controllable spin-dependent electron hoppings, which is found to cause a blockade of spin current with little influence on charge current. We have considered (1) the spread of a wave packet of both spin and charge and (2) the spin and charge currents induced by a spin-dependent voltage bias. It is found that the spin-charge separation plays a crucial role in the spin-current blockade, which may be utilized to observe the spin-charge separation directly.

• Received 2 October 2008

DOI:https://doi.org/10.1103/PhysRevB.78.193105