Engineering of hole-spin polarization in nanowires

We present a theoretical study of Zeeman spin splitting for quasi-onedimensional valence-band edges in cylindrical nanowires subject to a magnetic field parallel to the wire direction. The interplay between quantum confinement and strong spin-orbit coupling in the valence band gives rise to a controllable large variation of the effective g-factor for single wire levels. A direct correspondence is established between values for hole g-factors and characteristic spin-polarization profiles for wire-level bound states. The correlation between hole spin splittings and polarizations is mapped over the range of spin-orbit coupling strengths present in typical semiconductor materials. We propose to use nanowire subband edges as a versatile laboratory for experimental and theoretical study of the complex spin properties exhibited by quantum-confined holes.