Confinement In Wells Research Articles

Quantum propagation and confinement in 1D systems using the transfer-matrix method

The aim of this article is to provide some Matlab scripts to the teaching community in quantum physics. The scripts are based on the transfer-matrix formalism and offer a very efficient and versatile tool to solve problems of a physical object (electron, proton, neutron, etc) with one-dimensional (1D) stationary potential energy. Resonant tunnelling through a multiple-barrier or confinement in wells of various shapes is particularly analysed. The results are quantitatively discussed with semiconductor heterostructures, harmonic and anharmonic molecular vibrations, or neutrons in a gravity field. Scripts and other examples (hydrogen-like ions and transmission by a smooth variation of potential energy) are available freely at http://www-loa.univ-lille1.fr/∼pujol in three languages: English, French and Spanish.

Switches with double carrier confinement structures for multiple-valued logic applications

Two switching devices with different double carrier confinement structures were fabricated. One is a GaAs switch with double InGaP barriers, another with double GaAs-InGaAs delta-doped (-doped) quantum wells. In the characteristics of the former, because of the two-step barrier lowering induced by the processes of the carrier charging to the injection junction and carrier confinement in wells, a double S-shaped negative differential resistance (NDR) phenomenon is observed after the onsets of successive avalanche multiplications. However, only a single NDR performance is obtained in the characteristics of the latter due to one-step barrier lowering, even though successive avalanche multiplications also occur in the device operation.