We discuss the optical properties metal nanoforests - a composite metamaterial in which silver nanowires are aligned inside a finite-thickness dielectric host medium. Using finite-element modelling and a self-consistent extraction of effective-medium parameters, we find that this structure can enable an effective optical diamagnetic response that is orders of magnitude stronger compared to that of naturally occurring diamagnetic materials. Our analysis reveals that there is a frequency region where the nanoforest exhibits strong diamagnetic response while simultaneously allowing for high transmission of incident electromagnetic waves. Our analysis shows that the phenomena are robust to the presence of disorder, in the occurrence of which it can still facilitate high figure-of-merit diamagnetic responses. © 2009 SPIE.

A comprehensive theoretical study of the optical properties and switching competence of double-shell photonic crystals (DSPC) and doubleinverse-opal photonic crystals (DIOPC) is presented. Our analysis reveals that a DIOPC structure with a silicon (Si) background exhibits a complete photonic bandgap (PBG), which can be completely switched on and off by moving the core spheres inside the air pores of the inverse opal. We show that the size of this switchable PBG assumes a value of 3.78% upon judicious structural optimization, while its existence is almost independent of the radii of the interconnecting cylinders, whose sizes are difficult to control during the fabrication process. The Si-based DIOPC may thus offer a novel and practical route to complete PBG switching and optical functionality.

Recently there has been a considerable interest in metamaterial waveguide structures capable of dramatically slowing down or, even, completely stopping light. Here, we shall explain in some detail the working principle behind the deceleration and/or stopping of light in metamaterial structures, and review the various, metamaterial-enabled, methods that have been proposed thus far towards achieving such a goal. Further, we will concisely describe how one can construct zero-loss metamaterials over a continuous and broad (but not infinite) range of frequencies, which is an essential prerequisite for any slow-light system. Moreover, it will be explained that inside such waveguide structures light can in principle be stopped (zero group velocity, νg = 0) even in the presence of losses. By nature, metamaterial-enabled schemes for stopping/storing light invoke solid-state materials and, as such, are not subject to low-temperature or atomic coherence limitations. Furthermore, these methods simultaneously allow for broad bandwidth operation, since they do not rely on group index resonances; large delay-bandwidth products, since a wave packet can, in principle, be completely stopped and buffered indefinitely; and (for the case, in particular, where a negative-index metamaterial is used) high, almost 100%, in/out-coupling efficiencies. Thus, we conclude that these methods for trapping photons, which can be realised using existing technology, could open the way to a multitude of hybrid optoelectronic devices to be used in 'quantum information' processing, communication networks and signal processors and may conceivably herald a new realm of combined metamaterials and slow light research. © 2009 SPIE.

We review recent progress in the realm of ultra-slow and stored light inside metamaterial waveguides. We elucidate a number of critical issues pertaining to the study of light propagation in various slowlight metamaterial structures. © 2008 Optical Society of America.

We provide an overview of 'trapped rainbow' techniques for stopping light. We show that guided modes with real propagation consrtant and complex frequency can be 'trapped rainbow'-stopped even in the presence of waveguide losses. © 2009 Optical Society of America.

A comprehensive investigation of the optical properties of a composite metamaterial in which silver nanowires are aligned inside a finite-thickness dielectric host medium is presented. Using a rigorous finite-element based modelling approach, together with a self-consistent process for the extraction of effective-medium parameters, we find that this structure can enable an effective optical diamagnetic response that is orders of magnitude stronger compared to that of naturally occurring diamagnetic materials. Interestingly, our analysis reveals that there is a frequency region where the nanoforest exhibits a strong diamagnetic response while simultaneously allowing for high transmission of incident electromagnetic waves. We examine the physical origin behind the magnetic properties of this structure, as well as its resilience to fabrication imperfections. Our analysis shows that the structure is robust to the presence of disorder, in the occurrence of which it can still facilitate high figure-of-merit diamagnetic responses. © 2009 IOP Publishing Ltd.

Using finite-difference time-domain (FDTD) simulations we investigate the propagation of light pulses in waveguides having a core made of a negative-refractive-index metamaterial. In order to validate our model we carry out separate simulations for a variety of waveguide core thickness. The numerical results not only qualitatively confirm that light pulses travel slower in waveguides with thinner cores, but further they reveal that the effective refractive indices experienced by the propagating pulses compare favourably with exact theoretical predictions. We also examine the propagation of light pulses in waveguides with adiabatically, longitudinally varying core refractive index. The effective refractive indices extracted from these simulations confirm previous theoretical predictions while, both a slowing and an increase in the amplitude of the pulses are observed. © 2009 IOP Publishing Ltd.

We review recent progress in the realm of ultra-slow and stored light inside metamaterial waveguides. We elucidate a number of critical issues pertaining to the study of light propagation in various slowlight metamaterial structures. © 2008 Optical Society of America.

We review recent progress in the realm of ultra-slow and stored light inside metamaterial waveguides. We elucidate a number of critical issues pertaining to the study of light propagation in various slow-light metamaterial structures. ©2008 Optical Society of America.