Cost effective multi-wavelength light sources are key enablers for wide-scale penetration of gas sensors at Mid-IR wavelength range. Utilizing novel Mid-IR Si-based photonic integrated circuits (PICs) filter and wide-band Mid-IR Super Luminescent Light Emitting Diodes (SLEDs), we show the concept of a light source that covers 2.5…3.5 μm wavelength range with a resolution of <1nm. The spectral bands are switchable and tunable and they can be modulated. The source allows for the fabrication of an affordable multi-band gas sensor with good selectivity and sensitivity. The unit price can be lowered in high volumes by utilizing tailored molded IR lens technology and automated packaging and assembling technologies. The status of the development of the key components of the light source are reported. The PIC is based on the use of micron-scale SOI technology, SLED is based on AlGaInAsSb materials and the lenses are tailored heavy metal oxide glasses fabricated by the use of hot-embossing. The packaging concept utilizing automated assembly tools is depicted. In safety and security applications, the Mid-IR wavelength range covered by the novel light source allows for detecting several harmful gas components with a single sensor. At the moment, affordable sources are not available. The market impact is expected to be disruptive, since the devices currently in the market are either complicated, expensive and heavy instruments, or the applied measurement principles are inadequate in terms of stability and selectivity.
Most of the research work related to photonic crystal fibres has to date been focused on silica based fibres. Only in the recent years has there been a fraction of research devoted to fibres based on soft glasses, since some of them offer interesting properties as significantly higher nonlinearity than silica glass and wide transparency in the infrared range. On the other hand, attenuation in those glasses is usually one or more orders of magnitude higher that in silica glass, which limits their application area due to limited length of the fibres, which can be practically used. We report on the development of single-mode photonic crystal fibres made of highly nonlinear lead-bismuth-gallate glass with a zero dispersion wavelength at 1460 nm and flat anomalous dispersion. A two-octave spanning supercontinuum in the range 700–3000 nm was generated in 2 cm of the fibre. In contrast to the silica glass, various oxide based soft glasses with large refractive index difference can jointly undergo multiple thermal processing steps without degradation. The use of two soft glasses gives additional degrees of freedom in the design of photonic crystal fibres. As a result, highly nonlinear fibres with unique dispersion characteristics can be obtained. Soft glass allow also development of fibres with complex subwavelength refractive index distribution inside core of the fibre. A highly birefringent fibre with anisotropic core composed of subwavelength glass layers ordered in a rectangular structure was developed and is demonstrated
In recent years, several groups have investigated the use of Proximal Spatial Light modulation (PSML) as an alternative fiber optic imaging technique. In PSLM, the light exiting the distal end of the fiber optic endoscope can be focused, without any distal micro-optics or micro-mechanics, on any point within the Field Of View (FOV) via spatial modulation of the light before it is coupled in at the endoscope’s proximal end. In previous work, we reported on the custom design of a Coherent Fiber Bundle made with soft glasses (as opposed to the commercially available optical fibers used by other groups) to be used with PSLM. In this paper we present the results of the numerical characterization of the Coherent Fiber Bundle fabricated according to our design. We investigate the CFB’s modal propagation characteristics as well as its imaging properties (FOV and point spread function). Our numerical characterization also takes into account fabrication induced defects such as variations in core size, core shape (ellipticity) and lattice constant. Realistic values for the defects were obtained via SEM images of the fabricated CFB’s cross section. We find that noise on the wave front of the field exiting the distal end of the CFB causes a much larger deterioration of the point spread function than amplitude noise. And while we find that variations in core shape have the largest impact on the CFB’s propagation characteristics, our results indicate that this negative impact could be negated if the elliptical cores were aligned along a common axis.
Thermally stable tellurite, lead-bismuth-gallium oxides based boron-silicate and lead-silicate glasses dedicated for multiple thermal processing are presented. The glasses are successfully used for the development of photonic crystal fibers, nanostructured gradient index lenses, all-solid microstructured fibers as well as refractive or diffractive micro-optical elements with ultra-broadband transmission.
The main goal of this work was to examine the possibility of fabrication of glassy diffractive optical elements for application in the near-infrared and mid-infrared spectral ranges. In the paper we focused on fabrication of Fresnel lenses with use of the hot embossing process. Lead-bismuth-gallium oxide and tellurite glasses were used in the experiment. Both types of glasses possess high transmittance from the visible up to mid-infrared (0.4÷6.5μm). Fused silica element was used as the mold, which was fabricated with standard ion etching method. The elements presented in this work were fabricated in a static process with the use of low pressure. The quality of the fabricated elements was examined with white light interferometer.
In this paper we report on the development of diffractive and refractive micro optical components devoted to MidIR
applications. As a material we use a customized heavy metal oxide glasses with high transmission in the range
0.6÷6.0μm. Optimization of the glass composition in four- and five-component oxide systems for a broadband
transmission window is difficult due to their excessive crystallization susceptibility. Several metals and alloys were
tested for their suitability as a stamping medium. Optimal performance was obtained for selected brass and steel stamps,
as well as for pure silica stamps. As a technology testboard we have developed 1D and 2D diffractive gratings with a
minimum feature size of 5μm as well as Fresnel microlenses with a diameter of 200μm. The quality of the embossed
elements was verified by comparison of the master and replicated elements using a non-contact white light
We present a novel approach to the fabrication of diffractive optical elements. Unlike traditional diffractive optical
elements, the different phase shifts are obtained through a refractive index variation by using different types of glass.
This approach results in a completely flat element which is easy to integrate with other optical components. For
fabrication of the test DOE structures we have used the stack-and-draw technique. This method, which was originally
developed for the fabrication of photonic crystal fibres, has been modified to allow the fabrication of nanostructured
micro-optical components. In this paper we present the results from proof of concept periodic checkerboards fabricated
on a square and hexagonal lattice with feature sizes of 8μm and 46μm. The components were fabricated from two types
of rods made of the low refractive index silicate glass and the high refractive index of lead-silicate glass. The measured
characteristics of the fabricated components are presented The influence of fabrication-induced structure distortions on
the optical performance of the components is discussed.
The development of all-solid photonic crystal fibers for nonlinear optics is an alternative approach to the air-glass solid
core photonic crystal fibers. The use of soft glasses ensures a high refractive index contrast (>0.1) and a high nonlinear
coefficient of the fibers. In addition, the manipulation of the subwavelength structure of the core of a photonic crystal
fiber allows significant modification of its dispersion characteristics and efficient generation of supercontinuum with
various femtosecond and nanosecond sources. The development of all-solid photonic crystal fiber allows very accurate
control of all the parameters of the developed fiber in very good agreement with the design criteria.
In this paper, we report on the dispersion management capabilities in all-solid photonic crystal fibers with nanostructured
cores using thermally matched glasses, which can be jointly processed using the stack-and-draw fiber fabrication
technology. We consider a photonic crystal fiber made of the high index lead-silicate glass SF6 and the in-house
synthesized low index silicate glass NC21. The NC21 glass plays the role of low index inclusion in the photonic cladding
and a nano-inclusion in the core of the fiber. The final dispersion profile of the photonic crystal fiber is determined by
the low index nano-inclusion in the core with diameter in the range 100-500nm. The dispersion profiles are modeled for
a theoretical structure and for the developed fiber. Supercontinuum generation is expected and numerically confirmed for
the developed fiber in the range 1150-1500nm with flatness below 1dB. The fiber is dedicated for supercontinuum
generation with 1550nm laser sources.
We present the development of a large core multimode photonic crystal fibre with hyperspectral transmission that covers
the visible, near and (in part) mid infra-red wavelength ranges (400-6500 nm). We have optimised the composition of a
heavy metal-oxide glass based on the PbO-Bi2O3-Ga2O3 system modified with Nb2O5, Ta2O5, SiO2, GeO2, BaO, CdO, Na2O
and K2O. The optimised glass shows good transmission up to 6 μm as well as good rheological properties that permits
multiple thermal processing steps in an optical drawing tower without crystallisation. The selected glass is synthesized inhouse
and has been used for fibre development. We have fabricated a multi-mode photonic crystal fibre with an effective
mode area of 295 μm2. The photonic cladding is composed of 8 rings of air holes with a fill factor of 0.46. The transmission of a hyperspectral spectrum is experimentally verified using a broadband source. The attenuation of the fibre and its
sensitivity to bending losses is presented.
In this paper we report on design, manufacturing and characterization of microstructured optical fibers made of highly
non-linear tellurite glasses and devoted to supercontinuum generation. The tellurite glass labeled TWPN/I/6 is
synthesized in oxide system of 65TeO2-28WO3-5Na2O-2Nb2O5 [mol%]. The full characteristics of optical, thermal and
mechanical properties of this glass has been performed. Due to a very high resistance for devitrification during multiple
thermal processing the glass has been successfully used for PCF manufacturing by the stack-and-draw technique. The
manufactured fibers are characterized by the zero dispersion wavelength (ZDW) ranged from 1630 up to 2100nm.
Spectrum broadening in the range of 830-1100nm is observed for pump with 100 fs pulses at wavelength 919nm and
average power of 615mW.
In this paper we propose to structure a core of the photonic crystal fiber to tailor its dispersion properties. In this case the core is
composed of subwavelength rods of two types of glasses or air capillaries. We consider in the simulations two thermally matched
glasses SF6 and NC21 with a high contrast of refractive indexes over 0.1. We study an influence of core structure in terms of the
material and the nano-sized rod diameter on fiber dispersion. We show that a properly nanostructured core can significantly shift
ZDW of the fiber. Supercontinuum generation with developed PCFs is presented.
In this paper results of soft glass single mode photonic crystal fibers (PCF) fabrication are presented. Using "stack and
draw" technique a few kinds of PCFs (various core sizes and filling factors) made of multicomponent glasses has been
successfully fabricated. Two glasses, developed in-house at the Institute of Electronic Materials Technology (ITME),
have been used. High refractive index (nD=1.94) lead-bismuth-gallate glass (PGB-08) and borosilicate glass (NC21A).
We have achieved attenuation 3.9 - 5.1dB/m (λ=806nm) for fibers made of NC21A glass and 15dB/m (λ=632.8nm) for
PBG08 glass. Glasses attenuation: NC21A - 3.2dB/m, PBG-08 - 14.5dB/m. Fibers have very regular photonic cladding
with filling factor in range 0.2 - 0.7.
In this work we designed and made a photonic crystal structure with a photonic band gap around 532 nm wavelength.
The structure was to be made from two commercially available glasses. Both should have similar temperature
coefficients (alpha), also melting and softening temperatures should be as close as possible in order to thermally process
both glasses together. In addition the refractive indexes of chosen glasses should be as different as possible in order to
facilitate a wide band gap. The pair of glasses that met those requirements is LLF1 and SF6 produced by Schott. For
those two glasses we performed a series of computer simulations using MIT MPB software. After checking various
structures the widest band gap for the 532 nm wavelength was found for the hexagonal structure of high dielectric
constant rods in low index material with a linear fill factor of 0.12 and a lattice constant 3.75 μm. This structure was
manufactured using the stack and draw method. The measurements of the final structure made by ESM show that it is
regular, with diffusion between glasses at the manageable level. This assures that manufacture process is repeatable.
In this paper we report on design and development of three types of the soft oxide glasses devoted to microstructured
optical fibers manufacturing. The lead-bismuth glasses are synthesized in three-component oxide system of PbO-Bi2O3-
Ga2O3 and in a complex five-component oxide system of SiO2-Ga2O3-Bi2O3-PbO-CdO. The tellurite glasses are
synthesized in oxide system of TeO2-WO3-PbO-Na2O-Nb2O5 with various concentration of WO3 (5-38%mol) and PbO
(0-18%mol). Measurements of glass transmittance are performed over the range 200nm-10μm. Linear thermal expansion
coefficients and characteristic temperatures of glasses are determined based on dilatometer and Leitz heat microscope
measurements. A use of Differential Scanning Calorimetry (DSC) method and crystallization tests (isothermal treatment)
allows estimating the thermal stability of the glasses and susceptibility to crystallization. As a reference, similar
measurements are performed for commercially available lead-silicate glasses SF57 and SF6, which are considered for
development of nonlinear microstructured fibres. The glasses with an optimum resistance for devitrification during
multiple thermal processing are selected among all developed glasses for further fibre development. We present a
method for development of preform and subpreform elements as tubes, capillaries and rods used in the stack-and-draw
technique of the fiber manufacture. We report also successful development of subpreform components of
microstructured fibers based on selected tellurite and lead-bismuth glasses.
In this paper we report on the fabrication of a non-symmetric double core microstructured fiber made of in-house
synthesized silicate glass. The micro-structured fiber uses three rings of holes around two cores separated with a single
hole. This fiber has a birefringence of about 10-3 at 1.5 μm and zero dispersion wavelengths at 1.3- 1.5 nm range.
For experimental verification of nonlinear properties of the fiber we use a femtosecod Ti:Sapphire oscillator emitting in
the range of 750-900 nm in the normal dispersion regime of the pumped fiber. Measurements we performed with
excitation of one of the core and readout at the output from both cores separately. Registered spectra show a strong
coupling between cores and there is no evident difference between signals for excited or other core. Generated spectrum
is flat and relatively narrow, which is a result of pumping in normal region of fiber dispersion as we predicted with
We demonstrate the 3%mol ytterbium doped phosphate glass air-clad photonic crystal fibre (PCF) laser of 43 cm length
in single-mode operation. The fabrication and testing of the fibre laser is introduced. The laser generates from the 12 μm
core of photonic microstructure at wavelength of 1030 nm. Near 4-W output power and 14.6% slope efficiency against
the launched pump power is demonstrated in preliminary characterization.
In this paper we report on the fabrication and characterization of a double glass micro-structured fiber with low index core and photonic cladding made of high index micro-rods. Micro rods are made of lead-oxide F2 commercially available glass (SCHOTT Inc.) with a refractive index nD=1.619, while as background we use a borosilicate NC21 glass with a refractive index nD=1.533. The fiber cladding is composed of 8 rings of F2 glass micro rods ordered in hexagonal lattice. A core is created by replacement of seven F2 rods with NC21 rods. A fabricated fiber has a linear filling factor of 0.75 and micro rods diameter of 1.2 μm. A core has a diameter of 3.7 μm while cladding and total fiber diameter are 42,6μm and 120 μm, respectively.
Using supercontinuum source we have measured transmission properties of the fabricated fiber. Based on measurements of the fiber samples of 18-80 cm long we have identified two photonic band gaps. Fist band gap is localized in visible range at 610 nm central wavelength. The second broadband photonic band gap is localized in near infrared and it is 80 nm wide at 840 nm central wavelength.
In this paper we report on use stack and draw technique to develop volume 2D photonic crystals made of two types of
soft glasses with a large difference of refractive index. Existence of partial photonic bandgap in the material is predicted
Recently we have fabricated at Institute of Electronic Materials Technology (ITME) a microstrucuted fiber made of silicate glass NC21A synthesized in-house at ITME. Fabricated fiber is build of three rings of holes around slightly elliptical core (2.6 μm x 3.4 μm). Dispersion properties of the fiber are calculated based on real structure with biorthonormal basis method. Fabricated fiber has a birefringence at the level of 10-3 at 1.5 μm. A zero dispersion is achieved for the wavelengths 860 nm and 870 nm, respectively.
In this fiber, pumped with 100 fs pulses with energy of nJ level, ultra broadband supercontinuum generation in the range 400 - 1600 nm has been achieved.
In this paper we report on fabrication of all-Solid photonic Cladding and Air Core fiber (SCAC fiber). As far as we know it is a first reported fabrication of such PCF. Microrods are made of commercially available lead-oxide F2 glass (SCHOTT Inc.) with a refractive index nD=1.619, while as background we use a borosilicate NC21 glass synthesized in-house at ITME with a refractive index nD=1.533. A fabricated fiber has a lattice constant of Λ≈7.49μm and microrods diameter of d≈4.0μm. Air core has a diameter of DR=3.67μm and total fiber diameter is Dfiber=123.80μm.
Photonic crystals are wavelength-scale periodic structures built from dielectrics with different refractive indexes As
standard 2D photonic crystals are fabricated by lithographic methods, but in this case only planar structure can be
obtained. We have adapted stack and draw technique that is usually used for photonic crystal fiber fabrication to develop
volume 2D photonic crystals.
Technology allows fabrication of high contrast structures with air holes as well as low contrast solid-all structures where
air holes are replaced with glass micro rods of refractive index. Use of soft glasses with a high difference in refractive
index allows development of a structure where partial photonic band gap exists. The proposed method offers possibility
of fabrication volume 2D photonic crystal with a diameter in the order of 1 mm and height of a few mm. Large area
photonic crystals are very attractive as new optical material named 'photonic glass' with built-in photonic bandgap
functionality. Preliminary fabrication test were performed for two pairs of soft glasses NC21/F2 and SK222/Zr3. The
considered glasses are thermally matched and are synthesized in-house except of F2 glass (standard Schott glass).
Obtained structures are regular with some defects on the borders between intermediate performs. Some glass diffusion is
observed between Zr3 and SK222 glasses. With this technique a 2D photonic crystal with a hexagonal lattice was
fabricated with a pair of soft glasses SK222 and Zr3. Microrod diameter is 749nm and lattice constant 1110 nm.
Photonic crystal consists of 166421 elements (425 elements on diagonal) and its total surface is about field ~0,178mm2.
In this paper we report on the fabrication of a micro-structured fiber made of in-house synthesized silicate glass, with a
nonlinear Kerr refractive index of 4.0 10-15 cm2/W. The micro-structured fiber uses three rings of holes around a slightly
elliptical core with dimensions 2.6 μm x 3.4 μm. This fiber has a birefringence of about 10-3 at 1.5 μm and zero
dispersion wavelengths at 860 nm and 870 nm. Using this fiber we have demonstrated ultra broadband supercontinuum
generation in the range 400 - 1600 nm for 19.5 cm fiber sample pumped with 100 fs pulses with central wavelength of
755 nm and energy of 2 nJ. Broadband generation of 200 nJ in the range 650-850 nm with pulse energy on the level of
0.5 nJ is also observed with the same structure.
In this paper we report on progress in optimization of the material and structure of photonic crystal fibers for use as an
element of fiber sensor of strain and temperature. The fabricated photonic structures consist of elliptical-like holes
ordered in rectangular lattice. The rectangular lattice is applied to obtain global asymmetry of photonic structure with
two-fold geometry and to create birefringence of fiber. Elliptical air holes allows to increase birefringence in the
structure up to the order of 10 -2 for wavelength of 1.55 μm, theoretically. Additionally, rectangular lattice gives a better
control of elliptical air holes uniformity during fabricating process. For fabrication of the fibers we use NC21 borosilicate
glass. Use of high quality glass allows omitting problems with very high attenuation of the previously fabricated
highly birefringent photonic crystal fibers made of SK222 glass. With full vector plane-wave expansion method an
influence of structure parameters such as ellipticity of air holes and aspect ratio of rectangular lattice on birefringence
and modal properties of the fiber is studied. In this paper we present optimization of the fiber structure design, which
takes into account technological limits of fabrication of elliptical holes in fibers. Theoretical birefringence is compared
with experimental measurements. Experimental results already obtained allows to predict birefringence at the order of 10
-3 for wavelength of 1.55 μm for optimized photonic cladding of the fibers.
An all-solid photonic crystal fiber can be developed using two thermally matched glasses with one glass forming the
background, and the other the lattice of inclusions. Optical properties of all-solid holey fibers (SOHO) are sensitive to
the photonic cladding configuration, much the same as PCFs with air holes, and strongly depend on dispersion properties
of the materials used. When a high index contrast between the glasses is assured photonic crystal fiber can effectively
guide light with photonic band gap mechanism. This can be easily achieved when multicomponent soft glass is used for
We report on new developments of F2/NC-21 silicate all-glass PCFs. F2 is a commercially available glass (Schott Inc.)
with a high concentration of lead-oxide (PbO=45.5%) and the refractive index nD=1.619. It can be used both as the
background material and as a material for micro-rods (inclusions). A borosilicate glass (B2O3=26.0%) NC-21 glass has been
synthesized in-house at IEMT. NC21 has the index nD=1.533 and was used as the material for micro-rods (inclusions) or as
a background glass in the structures. The two selected glasses have a high index contrast equal to 0,084 at 1,55μm
wavelength. In this report we present new results on optimization of the filling factor d/Λ and reduction of the lattice
pitch Λ necessary to obtain efficient guidance at 1.55 μm.
The numerical analysis of SOHO F2/NC21 fibers has been carried out using a full-vector mode solver based on the
plane-wave expansion method. In our paper we report on photonic crystal fibers with two guiding mechanisms: an
effective index with a high index core (low index inclusions made of NC21 glass and F2 used as a background glass) and
a photonic band gap with a low index core (high index inclusions made of F2 glass and NC21 used as a background
Microstructured fibers with small core are successfully used as a medium for supercontinuum generation. Since light can
be confined in a small core a high density of energy in the fiber is obtained and stimulate nonlinear effects. Use of lead
multicomponent glass allows increasing nonlinear refractive index in the fiber and shape dispersion properties of the
fiber. In this case effective broadening of the spectrum can be obtained with less then 1 m of the fiber. In this paper we
present properties of photonic crystal fibers optimized for supercontinuum generation.
Double-clad photonic crystal fibre structure for laser applications is demonstrated. The double-clad structure of the fibre has the air-cladding with glass bridges of waists less than 500nm. The fibre was produced with phosphate glass and the core region was doped with ytterbium. The fibre was investigated and we found it to be monomode for generation wavelength of 1008nm. Whole fibre producing process including doped and undoped glass manufacturing and fibre drawing was held in Institute of Electronic Materials Technology.
A high birefringence in photonic crystal fiber is determined by a lattice type and shape of the holes. Based on the
simulations with use of biorthonormal basis method an optimized structure with rectangular lattice and elliptical-like air
holes has been selected. In this paper we present expected properties of the fiber. Preliminary experimental results are
Most photonic crystal fibers are made by stacking rods and tubes of a single glass. It is universal procedure to create an
air-glass perform which is drawn into a final fiber. It is difficult to obtain an air-glass structure with topology similar to
design one in practice. An alternative approach is to replace air holes with glass micro-rods in the considered structures.
Use of multicomponent glass allows obtaining a large contrast between microrods and background glass. As a result
index guiding and photonic bandgap fibers can be fabricated. In this paper we compare properties of air-glass and double
glass structures and report on fabrication double glass structures.
We present recent achievements in fabricating a two-dimensional (2D) photonic crystal in the form of a bundle of parallel micro- or nanowires embedded in glass matrix. The method is similar to that of sequential thinning used for fabrication of photonic crystal fibers. We discuss technological issues that aim at preservation of regularity of photonic crystal lattice and uniformity of wire diameters. Proper selection of a melting point of metal alloy and the range of temperatures of glass viscosity leads to reduction of regularity losses resulting from sequential processes of drawing. Measured distributions of crystal lattices, wire diameters and shapes of wires are used to simulate photonic band structure of fabricated crystals. This work is directed toward fabrication of a photonic crystal showing the negative refraction in the near infrared and visible spectral range.
In the paper we report on development of all-solid holey fibers. Numerical analysis of dispersion properties of such fibers is also presented. The periodic microrods that forms cladding are made of glass instead of air. Use of two or more multicomponent glasses in the fiber structure allow to manipulate refractive index contrast in the structures which is not possible in holey fibers. The all-solid holey fibers offer additional degree of freedom to the designer for determination of dispersion in fibers than in case of air-holes PCFs. Moreover a fabrication of all-solid PCFs allows to better control of geometry and uniformity of the cladding structure design.
We present experimental realization of elliptical-hole rectangular lattice photonic crystal fibres fabricated from multi-component glass. The photonic cladding has a lattice constant 2.17 μ and 3.72 μ for main axis, respectively and elliptical holes with ellipticity 2.14. The rectangular lattice is chosen to obtain two-fold geometry and to increase the global asymmetry of photonic structure, which enhance birefringence of fibre. Rectangular lattice allows also a better control of elliptical air holes uniformity during fabricating process. Fabricated fibres have a cladding with a rectangular cross-section. It allows for easy identification of the fibre's principal axes and orientation of the fibre with respect to directional measured perturbation like axial stress, bending force in sensor applications. Using a full vector plane-wave expansion method an influence of structure parameters such as ellipticity of air holes and aspect ratio of rectangular lattice on birefringence and modal properties of the fibres are studied. Potential applications of the fibres are discussed.
Most works on photonic crystal fibers with a photonic bandgap are concerned with structures made of silica glass with a hexagonal lattice. However, there are many other possible choices for the crystal structure of the fiber. In this paper, we study the optical properties of photonic bandgaps in a hollow-core photonic crystal fiber with a square lattice fabricated from multi-component glass. A composition of oxides was chosen to obtain a refractive index contrast higher than in fused silica fibers. The core size of the fiber is 11 microns and the cladding is made of an array of 17 x 17 air capillaries. A full-vector mode solver using the biorthonormal basis method is employed to analyze the modal properties of the fiber. We verify the guiding properties of the fiber by FDTD simulations. The transmission properties for several lengths of the fiber were measured by using broadband light from a nanosecond-pulse supercontinuum source and an optical spectrum analyzer. Preliminary results show that light is guided around 1650 nm. Possible modifications of the structure and potential applications will be discussed.
A range of integrated fiber optic structures - lightguides, image guides, multicapillary arrays, microstructured (photonic) fibers - manufactured in the Institute of Electronic Materials Technology (ITME) is described. All these structures are made of multicomponent glasses (a part of them melted in ITME). They can be manufactured in similar multistep process that involves drawing glass or lightguide rods and tubes preparing glass performs, stacking a bundle with rods and (or) tubes, drawing multifiber or multicapillary performs. Structure formation, technological process, characterization and applications of different integrated structures are presented.
The properties of photonic crystal fibers are determined by the structure of photonic cladding: filling factor, type of lattice and shape of air holes. The dispersion and modal characteristics of the fiber can be modified by adding an additional lattice of glass micro-rods with a refractive index higher than the glass substrate. We have fabricated a solid-core photonic crystal fiber with a double photonic cladding composed of air holes and glass micro-rods, where a high index multicomponent glass is used for the micro-rods. As a reference a fiber with similar parameters and a single lattice of air holes is fabricated. The fiber cladding is composed of 17 x 17 air holes and micro-rods ordered in square lattice. In this paper, we study the optical properties of photonic crystal fiber with single and double lattices. FDTD method and a full-vector mode solver based on biorthonormal basis method are used for fiber analysis. Possible modifications of the structure and potential applications will be discussed.
In photonic crystal fiber technique a free choice of microstructure allows flexible design of multicore waveguides. In this paper we study properties of a double-core fiber with square and hexagonal lattices. They can be modified with local changes of a structure. Variable size of the central hole that separates cores influences mode coupling properties. Full-vector mode solver using the biorthonormal basis method is employed to analyze guiding properties of the double-core fiber. In FDTD numerical simulations we study coupling efficiency in fibers with various crystal structures. We present experimental realizations of solid double-core photonic crystal fibers fabricated from multi-component glass. Composition of oxides is chosen to obtain higher refractive index than available in fused silica and relatively low-loss guidance when compared to other silicate glasses. Transmission properties of double-core fibers are measured, inter-core coupling mechanism and possible applications are discussed.
The freedom in choosing a crystal structure of the photonic fiber makes possible to manufacture fibers with more than one core. In this paper we present simulations of the characteristics of a double-core photonic crystal fiber with a square lattice. Such fiber can be used in telecomunication switches. The simulations of the modal structure were done using a vector method of biorthonormal bases. The results show that a double-core crystal, which exhibits mode coupling between cores fiber, can be designed. We present preliminary results of manufacturing of a double-core photonic fiber and measurements of its transmission characteristics.