Electrical manipulation of a hole ‘spin’–orbit qubit in nanowire quantum dot: The nontrivial magnetic field effects

Strong `spin'-orbit coupled one-dimensional hole gas is achievable in a Ge nanowire the presence of strong magnetic field. The field lifts two-fold degeneracy subband dispersions, so that effective low-energy dispersion exhibits coupling. Here, we study electrical `spin' manipulation quantum dot for both lowest and second dispersions. Using finite square well to model confining potential, calculate exactly level splitting qubit Rabi frequency electric-dipole resonance. coupling modulated longitudinal $g$-factor $g_{\rm so}$ not only non-vanishing but also dependent. Moreover, couplings dispersions have opposite dependences, results these two are totally different.