We report on the realization and characterization of a polymeric template sculptured in
photosensitive material, on a chemical inert surface. The structure is devoted to micro/nanoconfinement
and stabilization of a wide range of organic and nano-particle components with selfarrangement
properties at the nanoscale [1]. High quality morphology of a polymeric, micropatterned,
array is obtained by combining a, nano-precision level, optical holographic setup and a
multi-step chemico-physical process. The "universal" template represents the basic platform to be
filled with different organic materials, which can also include metallic nano-particles. The long
range self-organization is induced without making use of any kind of surface chemistry. Due to their
capability of exhibiting self organization, light responsive Liquid Crystals (LC) [2] and short pitch
Cholesterics LC [3] have been exploited, and experimental studies have been carried out in order to
investigate the photo-optical and elecro-optical response of obtained composite structures for the
realization of photonic devices. Finally, the possibility of including metallic nano-particles has been
also investigated, with the aim of inducing a "metamaterial" behavior of the realized structure.
The first experimental evidence of random laser action in a partially ordered, dye doped nematic liquid crystal
with long-range dielectric tensor fluctuations is reported. Above a given pump power the fluorescence curve
collapses and discrete sharp peaks emerge above the residual spontaneous emission spectrum. The spectral
linewidth of these emission peaks is narrow banded, typically around 0.5nm. The unexpected surviving of
interference effects in recurrent multiple scattering of the emitted photons provide the required optical feedback
for lasing in nematic liquid crystalline materials. Light waves coherent backscattering in orientationally ordered
nematics manifests a weak localization, strongly supporting the diffusive laser action phenomenon in the presence
of a gain medium. Unlike distributed feedback mirror-less laser, this system can be considered as a cavity-less
microlaser where the disorder unexpectedly plays the most important role, behaving as randomly distributed
feedback laser. The far field spatial distribution of the emission intensity shows a huge number of bright tiny
spots spatially overlapped and the intensity of each pulse strongly fluctuates in time and space. Here, we report
the main characteristics of this novel systems for various confinement geometries and under different conditions.
A brief presentation of boundary-less systems such as free standing and freely suspended dye doped nematic films
and droplets is also introduced, revealing unique emission features because of the complete absence of confining borders.
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