A method, originally due to Heitler, is utilized to extend the transfer Hamiltonian description to resonant tunneling for the purpose of calculating transition probabilities and general frequency response characteristics of coupled systems. The scanning tunneling microscope (STM) is treated as an example of a single barrier and an irradiated quantum well as an example of a double barrier. The saturation of the contact resistance in the STM is easily derived and a simple physical explanation for the high-frequency response of an irradiated double junction is presented. In the latter case, it is found that the cutoff in the frequency response for high frequencies is limited by the optical properties of the outer electrodes of the double barrier.
Citation: Physical Review B (Condensed Matter and Materials Physics)
Pub Type: Journals