Exciton-polariton confinement in Fibonacci quasiperiodic superlattice
SURFACE SCIENCE, 600 (18, SI):
4337-4341 (2006)23rd European Conference on Surface Science (ECOSS-23), Freie Univ,
Berlin, GERMANY, SEP 04-09, 2005.DOI: 10.1016/j.susc.2006.02.076
Abstract
We investigate the propagation of exciton-polaritons (bulk and surface
modes) in quasiperiodic superlattices of Fibonacci type, truncated at z = 0, where z is defined as the growth axis. For our purposes, the
Fibonacci structure can be realized experimentally by juxtaposing two
basic building blocks A and B, following a Fibonacci sequential rule.
Here A is the spatially dispersive medium modelled by a semiconductor
from the nitride family (GaN, for instance), which alternates with a
common dielectric medium B (sapphire). Our main aim is the investigation
of the modified optical properties of the exciton polariton modes for a
better understanding of the dynamics of the excitation in confined
systems. The dispersion relation shows a bottleneck profile for the
superlattice modes, whose behavior is similar to those found in the bulk
crystal. The Cantor-like energy spectrum is also investigated, and
scaling properties are shown for the Fibonacci quasiperiodic structure.
(c) 2006 Elsevier B.V. All rights reserved.