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Chapter I Brief Introduction...
dispersion and group velocity imposed in gratings, these structures also offer
new opportunities for generating soliton like effects over the short length
scales at low powers and short pulses.
Nanophotonics is again one prominent developing branch [108,109].
The application of nonlinear optics in photonic nanowires is discussed by
Foster et al [110]. Nanowaveguides, fabricated from glasses or
semiconductors, provide the maximum confinement of light for index guiding
structures enabling large enhancement of nonlinear interactions and group
velocity dispersion engineering. The combination of these two properties
make photonic nano wires ideally suited for many nonlinear applications such
as the generation of single cycle pulse and optical processing with sub-mW
powers.
Apart from the growth of organic crystals, the inclusion complexes,
mono and multilayered assemblies for example, Langmuir-Blodgett films and
poled polymers are considered. In the inclusion complexes, for instance, -
cyclodextric (-CD), a cyclic polysaccharide that crystallizes with spatial voids
in its three dimensional structure and the guest molecules such as N- methyl-
4 nitroaniline can be incorporated without destroying the crystal structure of
the host -CD. Due to the polar symmetry of -CD crystal, a net polar order of
the guest molecule is achieved [14]. For creating a polar material, the
approach of self-assembled mono and multilayer structures, for example,
Langmuir-Blodgett films have been developed. In this method the transfer of
monolayer films of an amphiphiles containing -chromophores from an air-
water interface to a solid substrate is carried out. This process can be
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