Using the effective-mass approximation and Floquet theory, we study the electron transmission over a quantum well in semiconductor heterostructures with Dresselhaus spin-orbit coupling and an applied oscillation field. It is demonstrated by the numerical evaluations that Dresselhaus spin-orbit coupling eliminates the spin degeneracy and leads to the splitting of asymmetric Fano-type resonance peaks in the conductivity. In turn, the splitting of Fano-type resonance induces the spin-polarization-dependent electron current. The location and line shape of Fano-type resonance can be controlled by adjusting the oscillation frequency and the amplitude of the external field as well. These interesting features may be a very useful basis for devising tunable spin filters.

• Received 5 November 2005

DOI:https://doi.org/10.1103/PhysRevB.73.085307