Optical properties of photonic crystals - New Jersey Institute of ...

CHAPTER 1 .
INTRODUCTION
Have you ever wondered what happens to electrons in semiconductor crystals or more so
in particular photonic crystals? If not then consider these facts. There are forbidden
energy states in a bandgap of the photonic crystal and because of the interference of
electron wave functions in the crystal lattice certain effects can be observed'. Scattering
at periodically arranged "dielectric atoms" might lead to an optical bandstructure, which
fundamentally alters the propagation of light as well as emission and absorption
processes in these mostly artificial structures. So it would good to consider a close
analogy of photons in so-called photonic crystals with other such related phenomena in
the InGAS range of spectrum i.e. 1.3 to 1.8microns.
Initial efforts 2 were motivated by the prospect of a photonic band gap, a frequency
band in three-dimensional dielectric structures in which electromagnetic waves are
forbidden irrespective of the propagation direction in space. An article in the Science
magazine3 said, "photonic crystals, tiny lattice-like structures that channel photons, may
pave the way for computers that calculate at light speed". The British Broadcasting
Corporation (BBC) 4 hinted that "this year, scientists made significant steps in their quest
to harness the power of photons in the same way that electrons are used in electronic
circuits". This year researchers have built photonic crystals and components, which can
manipulate light waves just as semiconductors manipulate electrical current and this
would lead to new types of high speed computers (next generation) and high speed
communication circuits capable of handling huge volumes of data, audio and video
signals.
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