| Abstract |
Interaction between light and matter is the main subject of nanophotonics.
For most systems, the interaction is electronic, that is, it involves changes in
the properties of electrons present in the system. Recently however, this approach
has been reversed [76, 29]: light instead of electrons will serve as the
information carrier. Thus, the confinement of photons in analogy with the
confinement of electrons is the fundamental alteration in these interactions.
This feature can be explained from a simple standpoint, that is, light presents
several advantages over the electron; it can travel in a dielectric material at
much greater speeds than an electron in a metallic wire and also photons
are not strongly interacting with each other as with electrons, which helps
reduce energy losses [27]. Hence, there is a strong need to design materials so
that they can affect the properties of photons, in much the same way that a
semiconductor crystal affects the properties of electrons. Both Yablonovitch
and John [76, 29] suggested that structures with a periodic variation in the
dielectric constant could influence the nature of photonic modes in a material.
In this sense, the answer to this need is met through the realization
of photonic crystals, which are artificial periodic nanostructures designed to
control and manipulate the flow of light.
Considering these three approaches mentioned above for nanoscale light confinement,
one comes across the main scope of this thesis which deals with the
fabrication and characterization of 3D linear and nonlinear photonic crystals.
In particular, we focus on 3D fabrication of high quality photonic structures
and on the design of stimulus-responsive materials for dynamic tuning of
photonic properties. The systems under study are woodpile based photonic
crystals fabricated by means of the two photon polymerization technique.
For this reason, the synthesis of novel linear and nonlinear materials suitable
for two photon fabrication, with proper optical and mechanical properties
necessary for the fabrication of precise 3D photonic structures will be the
starting point in our study. Following this, the study of the optical properties
of these novel materials in combination with the study of the optical
properties of the fabricated structures will lead us towards the complete characterization of such 3D photonic systems.
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Photonic Crystals with tunable properties
