Quantum Confined Semiconductors

Abstract

This overall objective of this research task was to push forward the state-of-the-art in utilizing semiconductor quantum dots in optical and optoelectronic devices of interest to the Air Force. The full potential of semiconductor quantum dots cannot be achieved by random formation and assembly processes. For narrow optical linewidths, suppressed thermal excitation, and tailored dot-to-dot interactions, the quantum dot size, composition and location needs to be precisely controlled to engineer the desired properties. Two complementary but distinct methods for fabricating uniform quantum dots with controlled dot/nanoparticle size, composition and location are proposed. 1) Nanopatterning and annealing of MBE grown planar InAs. 2) Synthesis of semiconductor nanocrystals by Supercritical Fluid CO2 process. In addition to the fabrication process development, a key objective is to model and characterize the fundamental physics and chemistry of these nanoscale heterostructures to provide the firm scientific basis for these materials to transition into advanced devices, such as detectors, lasers, optical communication and quantum computing.