Abstract
Owing to the tremendous progress in the past decade, semiconductor nanocrystals
that are grown by low-temperature solution-phase epitaxy have evolved into
highly promising material systems for optoelectronics with ever increasing interest
from the industry. However, fundamental challenges exist in conventional
nanocrystals hampering their energy-efficient optoelectronic devices. In this thesis,
we addressed important scientific problems and overcome various technological
hurdles through optical physics discoveries and innovative nanomaterial processing.
Specifically, we have proposed, designed and developed next generation
of nanocrystals that exhibit superior optical and material properties than those of
the conventional nanocrystals. Mastering intra- and inter-particle excitonic processes
in these nanocrystals and their hybrids empowered us to control and tailor
the desired photonic response. Our key achievements include demonstration of
record high modal gain coefficients and giant nonlinear absorption cross-section
in atomically-flat nanocrystals, ultralow-threshold all-solution processed quantum
dot lasers and unprecedentedly strong exciton transport in self-assembled
nanocrystals.
