Numerical study of spin relaxation in a quantum wire with spin-orbit interaction

The spin-relaxation length in quantum wires with spin splitting due to the lack of the structure inversion symmetry is numerically studied using a tight-binding model. The spin-relaxation length is sensitive to the spin-split subband structure in quantum wires. When the spin splitting is smaller than the subband separations, the quantized one-dimensional subbands have a well-defined spin and the spin-relaxation length is considerably enhanced with the decrease in the width.