Physics Colloquium: Low-Dimensional Semiconductor Nanostructures: Quantum wires, quantum dots and all that’s in between

Abstract:

Semiconductor nanotechnology makes possible the realization of electronic and photonic systems with reduced dimensionality, such as one-dimensional (1D) quantum wires (QWRs) and 0D quantum dots (QDs).  The reduced dimensionality can yield profound, deterministic modifications of fundamental processes such as electron-electron and electron-photon interactions, and may form the basis for novel electronic and photonic device technologies.  Here, we describe the evolution of the tailored physical properties of such systems with dimensionality between zero and one.  A specific model system, based on epitaxial growth on patterned surfaces and yielding a variety of such 0D-1D structures, is featured.  The observed properties of the corresponding 1D- to 0D-confined electrons and excitions, in particular energy band quantization and mixing, quantized electric conductance, Luttinger liquid correlations, generation of non-classical states of light, exciton-based cavity quantum electrodynamics and quantum wire/dot lasers, are described.  Future applications in quantum information technologies and single-photon integrated circuits are mentioned.