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1.
Buczynski R. Kujawa I. Kasztelanic R. Pysz D. Borzycki K. Berghmans F. Thienpont H. Stepien R. 《Laser Physics》2012,22(4):784-790
In this paper we report on the fabrication and characterization of an all-solid photonic band gap fiber with high contrast
and low index core. The fiber cladding is composed of high index lead-silicate rods while borosilicate NC21 glass is used
as a background glass. A 70 nm wide photonic band gap at 875 nm central wavelength is experimentally identified and compared
with a numerical model. We also present a novel method for photonic band gap measurement using a femtosecond pulsed laser.
The method is verified against standard one and discussed. 相似文献
2.
This article presents an investigation of the linear optical properties of a dual-core photonic crystal fiber with a square lattice made of a multicomponent glass in a second communication window. An experimental method based on intermodal interference was used to determine the effective refractive indices of higher-order modes, with knowledge of the fundamental mode dispersion. The effective refractive indices were also determined by an FDTD-based simulation and the obtained values provided a good agreement in comparison to the experimental results. The obtained results help to clarify the nonlinear spectral transformation processes observed in the same fiber at propagation in the higher-order modes. 相似文献
3.
We optimize the composition of tellurite glass for the manufacture of photonic crystal fibers with a large spectrum of transparency. The glasses, synthesized in four and five component (TeO2-WO3-Na2O-Nb2O5 and TeO2-WO3-PbO-Na2O-Nb2O5) oxide systems with variable contents of WO3 (5-38 mol%) and PbO (0-18 mol%), are designed and manufactured, and the transmission properties of the obtained glasses for the spectral range of 200 nm-7 μm have been determined. Thermal expansion coefficients and glass characteristic temperatures are determined by the dilatometer and Leitz heat microscope methods. Differential Scanning Calorimetry (DSC) measurements as well as crystallization tests by isothermal heat treatment are used to measure the thermal stability of the glasses and their ability to crystallize. Diffractive X-ray (XRD) measurements are used to determine the crystalline phases of the glass samples and the glasses with the highest resistance to recrystallization during thermal treatment were selected and used for the manufacture of photonic crystal fibers. 相似文献
4.
R. Stepien B. Siwicki D. Pysz G. Stepniewski I. Kujawa M. Klimczak R. Buczynski 《Optical and Quantum Electronics》2014,46(4):553-561
We report on characterization of a large solid core, photonic crystal fiber dedicated to broadband transmission range from visible to mid-infrared. We have fabricated a multi-mode photonic crystal fiber, made of a heavy metal-oxide glass based on the $\hbox {PbO}{-}\hbox {Bi}_{2}\hbox {O}_{3}{-}\hbox {Ga}_{2}\hbox {O}_{3}$ system, modified with $\hbox {SiO}_{2}$ and CdO, synthesized in-house, which shows good transmission up to $4.5\,\upmu \hbox {m}$ , as well as good rheological properties that permit multiple thermal processing steps without crystallization. The core of the fiber is created by replacement of central 60 tubes with solid rods. The photonic cladding is composed of 8 rings of air holes with a filling factor of 0.42. Simulation results shows that the fiber can be used for broadband transmission in the range of 430–3,000 nm. Calculated effective mode area of the fiber is $295\,\upmu \hbox {m}^{2}$ . We have measured attenuation of the fiber in the range 800–1,700 nm and its sensitivity to bending losses. Attenuation ranges from 1 to 4 dB/m in the considered range and bending losses are below 0.7 dB. 相似文献
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6.
R. Buczynski J. Pniewski D. Pysz R. Stepien R. Kasztelanic I. Kujawa A. Filipkowski A. J. Waddie M. R. Taghizadeh 《Opto-Electronics Review》2012,20(3):207-215
The development of all-solid photonic crystal fibres for nonlinear optics is an alternative approach to air-glass solid core photonic crystal fibres. The use of soft glasses ensures a high refractive index contrast (> 0.1) and a high nonlinear coefficient of the fibres. We report on the dispersion management capabilities in all-solid photonic crystal fibres taking into account four thermally matched glasses which can be jointly processed using the stack-and-draw fibre technique. We present structures with over 450 nm broadband flat normal dispersion and ultra-flat near zero anomalous dispersion below 5 ps/nm/km over 300 nm dedicated to supercontinuum generation with 1540 nm laser sources. The development of an all-solid photonic crystal fibre made of F2 and NC21 glasses is presented. The fibre is used to demonstrate supercontinuum generation in the range of 730?C870 nm (150 nm) with flatness below 5 dB. 相似文献
7.
D. Lorenc I. Bugar M. Aranyosiova R. Buczynski D. Pysz D. Velic D. Chorvat 《Laser Physics》2008,18(3):270-276
Processes resulting in supercontinuum generation in multicomponent glass photonic crystal fibers are reviewed in this paper. Multicomponent glass photonic crystal fibers are shown to have a broad transmission range, extending up to 4.5 μm in selected cases. Pumping with a 1240-nm femtosecond pulse at very low sub-nJ energies resulted in soliton formation and dispersive wave generation in a multicomponent PCF sample having a double-core square-lattice structure. These processes were described using a phase-matching model derived from the simulated dispersive properties of the fiber. Third-harmonic generation was observed in the radiation modes of a different cobweb sample with the simultaneous formation of a soliton in the NIR. 相似文献
8.
D. Lorenc M. Aranyosiova R. Buczynski R. Stepien I. Bugar A. Vincze D. Velic 《Applied physics. B, Lasers and optics》2008,93(2-3):531-538
The second order nonlinear refractive index n 2 of various multicomponent glasses was measured at the wavelength of 1240 nm close to the 1.3-μm fiber transmission window. With the refractive index covering the range from 1.45 to 2.3, a comparatively broad range of n 2 with values from 1.1×10?20 m2/W for boro-silicate based glass NC21 to 4.3×10?19 m2/W for lead–bismuth-gallate based glass PBG08 was measured using the Z-scan method. Considering the broad infrared transmission range of multicomponent glasses, these materials pose a great potential for future applications as photonic crystal fiber sources of infrared supercontinuum. 相似文献
9.
Bednarska K Wachowicz B Buczynski A 《Journal of photochemistry and photobiology. B, Biology》2000,55(2-3):109-112
UV-B irradiation of blood-platelet concentrates is used in transfusion practice to prevent the development of post-transfusion alloimmunization and inactivate viruses and bacteria in the concentrates. UV-B radiation may affect the blood-platelet metabolism and function; therefore we have investigated the effect of UV-B irradiation on free radical production in blood platelets. Our results show that exposure of pig blood platelets to UV-B radiation (0.36 and 1.08 J/cm2) induces the generation of free radicals measured by the chemiluminescence method (respectively 28 and 148.6% above the control). The superoxide radical level after UV-B irradiation measured by the cytochrome c reduction method shows only a slight increase (p > 0.05). Free radical generation induced by UV-B radiation is dependent partly on blood-platelet activation and enzymatic pathways, since we have shown that wortmannin, an inhibitor of phosphatidylinositide 3-kinase, reduces the level of radicals formed in blood platelets after UV-B irradiation. This indicates that free radicals generated in blood platelets after stimulation by UV-B radiation are involved in platelet activation and metabolism of platelet polyphosphoinositides. 相似文献
10.
Jaroslaw Buczynski 《Transformation Groups》2007,12(4):631-646
We give the full classification of smooth toric Legendrian subvarieties in P2n-1. We also prove that under some minor assumptions the group of linear automorphisms preserving a given Legendrian subvariety
preserves the contact structure of the ambient projective space. 相似文献