Project HERODOT: Hererogeneous quantum rod and quantum dot nanomaterials, towards a novel generation of photonic devices

2008-09-01 – 2012-08-31

Abstract

Recent progress in the fabrication of colloidal semiconductor nanocrystals has led to a wide range of quantum dots with a high oscillator strength, photoluminescence efficiency and size-tunable emission spectrum. The Herodot project (Heterogeneous quantum rod and quantum dot nanomaterials) encompasses a comprehensive research and training program on the opto-electronic properties of heterostructured nanomaterials based on quantum rod and dot building blocks. In particular, material systems of study are quantum dot molecules, binary quantum dot solids, superstructures of aligned quantum rods and hybrid organic/inorganic systems with specific band alignment (type-II heterostructures). The optical properties of these systems, e.g. polarizability, exciton lifetime and emission spectrum are determined by the delocalized, indirect nature of the exciton, while optical anisotropy can be achieved by alignment of quantum rods. Such systems can exhibit a large Stokes’shift, enhanced nonlinear refraction, and an absorbance and emission spectrum that can be tailored by the architecture of the superstructure and external fields. This forms a direct route to applications of these materials in optimizing light sources, next generation photovoltaics, and realizing fast and compact optical modulators and switches.