Defect-assisted resonant tunneling: A theoretical model

Defects are often taken as the cause of deviations in the current-voltage characteristics of heterostructures such as barrier or double barrier, and the so-called defect-assisted tunneling effect has been assumed to occur in certain cases. We present an analytical analysis of the tunneling effect which occurs through a barrier and which is assisted by an energy level associated with a defect. Moreover, we show that a negative differential resistance can occur using a single barrier in which a defect is located.