  We investigate double finger gate (DFG) controlled spin-resolved resonant
transport properties in an n-type quantum channel with a Rashba-Zeeman (RZ)
subband energy gap. By appropriately tuning the DFG in the strong Rashba
coupling regime, resonant state structures in conductance can be found that is
sensitive to the length of the DFG system. Furthermore, a hole-like bound state
feature below the RZ gap and an electron-like quasi-bound state feature at the
threshold of the upper spin branch can be found that is insensitive to the
length of the DFG system.
