109 research outputs found
New Trends in Amplifiers and Sources via Chalcogenide Photonic Crystal Fibers
Rare-earth-doped chalcogenide glass fiber lasers and amplifiers have great applicative potential in many fields since they are key elements in the near and medium-infrared (mid-IR) wavelength range. In this paper, a review, even if not exhaustive, on amplification and lasing obtained by employing rare-earth-doped chalcogenide photonic crystal fibers is reported. Materials, devices, and feasible applications in the mid-IR are briefly mentioned
Two-dimensional solitons with hidden and explicit vorticity in bimodal cubic-quintic media
We demonstrate that two-dimensional two-component bright solitons of an
annular shape, carrying vorticities in the components, may be
stable in media with the cubic-quintic nonlinearity, including the
\textit{hidden-vorticity} (HV) solitons of the type , whose net
vorticity is zero. Stability regions for the vortices of both types
are identified for , 2, and 3, by dint of the calculation of stability
eigenvalues, and in direct simulations. A novel feature found in the study of
the HV solitons is that their stability intervals never reach the (cutoff)
point at which the bright vortex carries over into a dark one, hence dark HV
solitons can never be stable, contrarily to the bright ones. In addition to the
well-known symmetry-breaking (\textit{external}) instability, which splits the
ring soliton into a set of fragments flying away in tangential directions, we
report two new scenarios of the development of weak instabilities specific to
the HV solitons. One features \textit{charge flipping}, with the two components
exchanging the angular momentum and periodically reversing the sign of their
spins. The composite soliton does not split in this case, therefore we identify
such instability as an \textit{intrinsic} one. Eventually, the soliton splits,
as weak radiation loss drives it across the border of the ordinary strong
(external) instability. Another scenario proceeds through separation of the
vortex cores in the two components, each individual core moving toward the
outer edge of the annular soliton. After expulsion of the cores, there remains
a zero-vorticity breather with persistent internal vibrations.Comment: 10 pages, 11 figure
Optical, magneto-optical properties and fiber-drawing ability of tellurite glasses in the TeO2-ZnO-BaO ternary system
The presented work is focused on the optical and magneto-optical
characterization of TeO2-ZnO-BaO (TZB) tellurite glasses. We investigated the
refractive index and extinction coefficient dispersion by spectroscopic
ellipsometry from ultraviolet, 0.193 um, up to mid infrared, 25 um spectral
region. Studied glasses exhibited large values of linear (n632 = 1.91-2.09) and
non-linear refractive index (n2 = 1.20-2.67x10-11 esu), Verdet constant (V632 =
22-33 radT-1m-1) and optical band gap energy (Eg = 3.7-4.1 eV). The materials
characterization revealed that BaO substitution by ZnO leads (at constant
content of TeO2) to an increase in linear and nonlinear refractive index as
well as Verdet constant while the optical band gap energy decreases. Fiber
drawing ability of TeO2-ZnO-BaO glassy system has been demonstrated on
60TeO2-20ZnO-20BaO glass with presented mid infrared attenuation coefficient.
Specific parameters such as dispersion and single oscillator energy, Abbe
number, and first-/ third-order optical susceptibility are enclosed together
with the values of magneto-optic anomaly derived from the calculation of
measured dispersion of the refractive index
Optical and structural properties of new chalcohalide glasses
New class of chalcohalide glasses has been prepared in the GeS2–In2S3–CsI system with regard to their potential non-linear properties. The study of glass-forming region was undertaken to select glassy compositions, which present high non-linear (NL) optical properties with a low two-photon absorption. Thermal analyses, structural examination by Raman spectroscopy, non-linear optical measurements were investigated as a function of CsI contents. Introduction of CsI has shifted the band-gap edge towards the blue region of the absorption optical spectrum and therefore has limited the two-photon absorption. Their NL refractive index n2 are 60 times higher than silica glasses without any NL absorption. Moreover, second harmonic signal was observed in thermally poled samples similar to silica glass. However, this second order non-linearity is not temporally stable
Non-linear optical properties of chalcogenide glasses measured by Z-scan
International audienc
Nonlinear optical properties of chalcogenide glasses: comparison between Mach–Zehnder interferometry and Z-scan techniques
International audienc
Third order nonlinear optical characterization of new chalcohalogenide glasses containing lead iodine
International audienc
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