Magnetic-field-induced resonant tunneling across a thick square barrier

Abstract
The spatial part of the wave function is calculated exactly for tunneling in a magnetic field, confined within a thick square barrier. Due to the presence of the field perpendicular to the current flow, transmission is heavily reduced and a threshold is found, based on very general kinematical arguments. However, magnetic-field-induced scattering states could be present, which have a high probability density inside the barrier giving rise to resonant tunneling. They are responsible for a strong dependence of the transmission on the energy and the angle of incidence of the incoming beam. These resonances are analyzed as a function of an applied external bias and the possibility of their appearance in the I-V characteristic is discussed. They certainly affect any typical time for tunneling, as shown in the limiting case of a totally reflecting magnetic barrier.