The Rashba field in a quantum channel produces spin splitting and population imbalance between spin-up and -down electrons. The channel resistance depends on the alignment between the applied field and the Rashba field because the applied magnetic field causes different mobilities for two types of spins. With an applied field of 2 T, the mobility difference between spin-up and -down electrons is 0.75%. (C) 2011 Elsevier B.V. All rights reserved.