Esaki Tunneling

Tunneling, between propagating electron states, at a semiconductor junction is discussed in terms of customary quantum transition theory for the matrix elements of the hamiltonian between the states representing reflection of an electron (in either band) from the junction. The coordinate representation for the wavefunctions of these states is investigated, and tunneling probabilities (ratios of transmitted to incident current) are found for the “elastic” process proposed by Esaki and for the “phonon-assisted” processes. It appears that the tunneling may be described as taking place in a central region of the junction thinner than the space charge region. Current-voltage characteristics are calculated both for elastic and for phonon-assisted tunneling.