Drawing on recent advances in understanding the origin of the photonic band gap observed in hollow core photonic
crystal fibers, we apply the photonic tight binding model to a high air filling fraction fiber. By studying the interdependent
effect of the apex, strut and air-hole resonators present in the photonic crystal cladding, we demonstrate that it
is possible for a second photonic band gap windows to extend significantly below the air-line, whilst the general
properties of the fundamental band gap remains relatively unaffected. We fabricate several hollow core fibers with
extremely thin struts relative to the apex size. All fibers exhibit two strong transmission windows that bridge the
benchmark laser wavelengths of 1064nm and 1550nm. These results pave the way to extend the guidance capability of
low-loss hollow core fibers.
We have developed an all-fiber system which we use to demonstrate slow and fast light based on electromagnetically
induced transparency in a 20 meter acetylene-filled photonic microcell. Using this system, 30 ns pulses of probe light
were delayed and advanced by up to 5 ns and 1 ns respectively. The delay/advance is tunable through the probe detuning
and the coupling Rabi frequency. Through optimization of experimental parameters such as acetylene pressure, coupling
laser power and decoherence rates it is shown that a pulse delay of 30 ns/m is possible. Limitations imposed on the fiber
length by resonance group velocity dispersion and spectral reshaping are also discussed. In addition to optical buffering,
we suggest a slow-light based fiber optical gyroscope with an enhanced signal-to-noise ratio of ~ 92.
Optical fiber sources have experienced a massive growth over the past ten years principally due to the compactness,
robustness and good spatial quality of such systems. Fiber sources now cover a large spectrum from visible to near
infrared helped on this point by the development of microstructured fibers (MOFs). A particular class of MOFs also
called hollow-core photonic crystal fibers (HC-PCFs) offers to get rid of silica's absorption thanks to band gap guidance
and therefore to extend transmission range of silica fibers. We propose here two all-fiber architectures based on HCPCFs
in view to generate mid infrared wavelengths by amplification of spontaneous Raman scattering (SRS) in gaseous
medium. We report on design, fabrication and characterization of two kinds of HC-PCF matching the architecture needs.