Dynamics of electronic transport in a semiconductor superlattice with a shunting side layer

Abstract

We study a model describing electronic transport in a weakly coupled semiconductor superlattice with a shunting side layer. Key parameters include the lateral size of the superlattice, the connectivity between the quantum wells of the superlattice and the shunt layer, and the conduction properties of the shunt layer. For a superlattice with small lateral extent and high quality shunt, static electric field domains are suppressed and a spatially uniform field configuration is predicted to be stable, results that may be useful for proposed devices such as a superlattice-based terahertz oscillators. As the lateral size of the superlattice increases, the uniform field configuration loses its stability to either static or dynamic field domains regardless of shunt properties. A lower quality shunt generally leads to regular and chaotic current oscillations and complex spatiotemporal dynamics in the field profile. Bifurcations separating static and dynamic behaviors are characterized and found to be dependent on the shunt properties.