ABSTRACT
In 1970 Tsuchiya and Esaki proposed a one-dimensional super lattice. At the same time they proposed the concept of resonant tunneling. They indicated that in such a structure the period is smaller than the electron mean free path and intriguing transport properties such as negative differential conductivity and Bloch oscillation can be realized. The singularities actually exhibit a decrease in current, giving rise to a negative differential resistance. Due to the development of the molecular beam epitaxy technology and the improving of the quality of the sample, the negative resistance can be observed not only at a low temperature but also at room temperature clearly. As for application, the advantage of the resonant tunneling diode is that the basic time related to the tunneling process is very short, generally taken as the reciprocal of the quasi-confined state in the quantum well.
