Nanostructured Materials for Controlling Light

Light control and modulation have applications in many different science and 
engineering fields. It would be interesting to note that one of the earliest 
proposals for anti-reflection coatings was by Lord Rayleigh in 1880. From 
then, the so called quarter wave stacks, graded index materials and more 
recently nanostructured materials were demonstrated as anti-reflection 
coatings. However, one proposal which has not been experimentally realized is 
the optical reflectionless potential. In this talk, I will mainly focus on our 
results on refractive index profiles conforming to reflectionless potentials. 
These structures show broadband, polarization and launch angle independent 
suppression of reflection. In addition to this property, they show negative 
group index over broad band. Consequences include superluminal transmission 
and pulse compression. If time permits, I will show results on light 
modulation and light harvesting using metamaterials.