We introduce an efficient method for slowing and stopping/storing light, which is based on wave propagation along a
slowly axially varying, adiabatically tapered, negative refractive index metamaterial heterostructure. We analytically
show that the present method can, in principle, simultaneously allow for broad bandwidth operation (since it does not
rely on group index resonances), large delay-bandwidth products (since a wave packet can be completely stopped and
buffered indefinitely) and high, almost 100%, in/out-coupling efficiencies. Moreover, by nature, the presented scheme
invokes solid-state materials and, as such, is not subject to low-temperature or atomic coherence limitations. This method
for trapping photons conceivably opens the way to a multitude of hybrid, optoelectronic devices to be used in 'quantum
information' processing, communication networks and signal processors, and may herald a new realm of combined
metamaterials and slow light research.
We perform numerical computations of photonic band structures of core-shell opal-based photonic crystals to explore the influence of structural parameters on the optical properties. In particular we consider variations of the refractive indices of the shell. Based on our results we propose a way of controlling the photonic band gap in this type of photonic crystal.