Coherent and sequential processes in resonant tunneling through a double barrier are theoretically analyzed by means of a magnetic field parallel to the interfaces. The use of a simple model for describing scattering effects and a generalized transfer Hamiltonian method allow us to conclude that presently available experimental information is restricted to the sequential regime. We show that, for systems with barriers narrower than the ones used in the published experiments, coherent tunneling becomes dominant on the sequential mechanism.

• Received 31 March 1989

DOI:https://doi.org/10.1103/PhysRevB.40.8548