NCN projects

Manager on the part of Faculty of Electrical Engineering BUT: Assoc. Prof. Marcin Kochanowicz, DSc, PhD, Eng.
Members of the consortium:

• Faculty of Electrical Engineering,
• AGH University of Science and Technology – leader

Project number: 2017/25/B/ST8/02530
Source of funding: National Science Centre (Poland)
Name of the program: OPUS 13
Duration of the project: 26.02.2018 – 25.02.2022

The aim of this project is to study the effect of rare-earth co-doping of a fluoroindate glasses enabling formation of optical fibers for application them in broadband amplified spontaneous emission sources and and fiber lasers emitting radiation in the range 1800-6000 nm. The primary task of research is to determine the impact of dopant concentration (lanthanide ions) in glasses on energy transfer mechanisms between rare-earth ions and the shaping of luminescence spectra in relation to fabricated waveguide structures. This objective of project is due to the hypothesis of the possibility of efficient emission (dopants and co-dopants lanthanides) in fluoroindate glasses with low-phonon energy approx. 510 cm-1. The literature analysis and experimental research, carried out by the author of the deduction, enable to selection of a suitable chemical composition of the glass and dopant concentration enable to efficient emission in glasses and optical fibers in near- and mid-infrared range. These issues are not investigated yet as particular and that is most important research aspect in point of view of modern optoelectronics.

• study the effect of co-doping with rare-earth ions of fluoroindate glasses on their spectroscopic properties.
• analysis of near and mir-infrared luminescence and energy transfer processes between rare-earth in fluoroindate glasses and active fibers,

• comparative analysis of luminescent properties of fluoroindate glasses doped with lanthanide ions and fabricated optical fibers
• development of technological parameters of the synthesis of fluoroindate glasses doped and co-doped withrare-earthh ions and determine the conditions of optical structure creation capable of broadband emission resulting from energy transfer between rare-earth ions.
• basic research regarding the analysis of luminescent properties of optical fibers made of flouroindate glasses, allowing the management of the shape of luminescence spectra.

Project manager: Assoc. Prof. Marcin Kochanowicz, DSc, PhD, Eng.
Contractor: Faculty of Electrical Engineering
Project number: 2019/35/B/ST7/02616
Source of funding: National Science Centre (Poland)
Name of the program: OPUS18
Duration of the project: 02.10.2020 – 01.10.2023

The research area of the project is in the field of one of the rapidly developing fields of science, which are photonic and concerns new constructions of multicore optical fiber characterized by broadband spontaneous emission (ASE) in the range of 1.0 – 2.1 µm. Sources of radiation characterized by ultra-wideband emission are necessary to use in e.g.: optical telecommunication (2nd, 4th telecommunication windows) medicine (OCT high resolution imaging) and metrological systems. Nowdays the special interest is emphasized into spectral regions 1.0-1.7 µm and 1.5-2.1 µm. Starting from OCT sources, extending the emission range (in the 1 µm band) increases imaging resolution, the 1.5-2.1 µm wavelength range (called eye-safe) is demanding because of the potential applications in both military and civil applications such as telemetry, optical laser systems (LIDAR – Light Detection and Ranging), microsurgery, medical diagnostics and monitoring of industrial and environmental pollution. Current solutions use optical parametric oscillators (OPO) and photonic fibers (supercontinuum). However, they work in pulse mode and usually require excitation with an expensive ns-fs laser. Therefore, new solutions are being sought to build compact broadband radiation sources operating in the near and mid-infrared range. The main aim of the project is to develop multicore optical fibers from germanate glasses characterized by ASE (continuous wave operation) in the range operating of: 1) 1.5.-2.1 µm – co-doping with rare earth (RE) ions, 2) 1.0-2.1 µm – glass-ceramic (GC) optical fibers. Ultra-broad emission will be obtained by superposition of emission bands from metals (Ni, Cr, Bi) and rare-earth (lanthanides) with power from tens to hundreds of mW.

• Development of multicore-core fibers with single cores doped with metals (Bi/Ni/Cr) and rare-earth (Yb/Nd/Er/Tm/Ho) elements which will be excited by the internal cladding and fulfill the condition of broadband emission in the 1.0-2.1 µm (1.7-1.4 µm and 1.5-2.1 µm) region.
• Development of multicore-core fibers in the extended range from 1 µm to 2.1 µm by the metals (Bi/Ni/Cr) and f-block (RE) elements co-doping and fabrication of a new multicore glass-ceramic fiber.

• Yb/Nd/Er/Tm/Ho co-doped multicore optical fibers with broadband ASE in the range of 1.5-2.1 µm.
• systematic analysis of the effect of the f
  • iber construction: RE-co-dopants concentration (donor-acceptor energy transfer analysis), number and position of the cores on their spectroscopic properties,
  • glass-ceramics optical fiber with ultra-broad ASE (combining emission from RE and Tm/Bi) in the range of 1.0-2.1 µm.

Project manager: Assoc. Prof. Jacek Żmojda, DSc, PhD, Eng.
Contractor: Faculty of Electrical Engineering,
Project number: 2016/21/D/ST7/03453
Source of funding: National Science Centre (Poland)
Name of the program: SONATA 11
Duration of the project: 19.01.2017 – 18.01.2020

The scientific aim of this project is to analyze luminescence properties of photonics glasses and optical fibers to determining an interaction mechanisms (energy transfer, plasmon resonance) of noble metal ions (Ag+, Au+) and rare earth ions, also to determining optical properties of these materials enable to shaping of luminescence spectra. Material scope of research results from the need to determine the correlation between the structure of glassy material and efficiency of coupling between metallic nanoparticles and rare earth elements placed in the same optical medium. In results, two main complementary phenomena influencing on the changes in emission properties in photonics glasses will be determined. One of them is the energy transfer between metal nanoparticles and rare earth ions resulting from partial absorption of pumping radiation by silver and gold ions and the second one is the enhancement of the luminescence signal by changing the local field of the rare earth sample resulting from the surface plasmon resonance of interacting metallic nanoparticles. In the project, development of thermally stable glasses characterized by vary phonon energy with good optical properties enable to forming optical fibers from them was planed. It should be noticed that condition of high thermal stability (lack of crystallization effect) will be fulfilled under modern optical fiber technology requirements. The next step is co-doping of fabricated photonic glasses (containing RE ions) with noble metal ions (Ag+, Au+) and analysis of their luminescence properties. A necessary complement to research is determining conditions of the forming process of nanoparticles as a result of heat treatment. Contribution to the collection of basic research is also the analysis of structural properties of glasses which enable obtaining metallic nanoparticles and forming their geometry in the controlled process of heat treating and also leading to shaping of luminescence properties of the matrix. Moreover, selection of a suitable chemical composition of the core glass and the dopant concentration (rare earth ions + noble metal) will allow the formation of metallic nanoparticles through a thermal treatment directly in the drawing process of optical fibers. Suggested issues comprise innovative character of basic research in the field of optoelectronics and nanophotonics, behind which there is the explanation of correlations that influence shape of the luminescence signal, which result from the local field enhancement (LFE) of the admixture and the energy transfer between metal particles and lanthanide elements. The fabrication of active fiber optic containing metal particles and comparing its luminescent properties with fabricated glasses is added value to planned research within the project.

• Analysis of luminescent properties of glass and optical fibers co-doped with nanoparticles and lanthanide ions.
• Study of local field enhancement resulting from localized surface plasmon resonance (LSPR) phenomenon.
• Investigation of the thermochemical reduction of silver nanoparticles on luminescent properties of optical fibers.

• Development of antimony-germanate glass co-doped with lanthanide ions and noble metal nanoparticles.
• Optimization of nanoparticles content in thermochemical reduction process leads to enhancement of luminescence.
• Determination of the impact of silver nanoparticles on optical, thermal and structural properties of glass and optical fibers.
• Detailed analysis of interaction mechanisms between nanoparticles and lanthanide ions in order to obtain plasmonic effect.
• Fabrication of antimony-germanate optical fibers with self-organized nanoparticles arrays at the surface of glass fibers.

Project manager: Łukasz Gryko, PhD, Eng.
Contractor: Faculty of Electrical Engineering
Project number: G/WE-IA/2/2021 (PB)
Source of funding: National Science Centre (Poland)
Name of the program: MINIATURA 5
Duration of the project: 15.12.2021 – 14.12.2022

The aim of the project is to de

• velop a control algorithm (based on the Monte Carlo method) for set of high-power LEDs (phosphor-converted and narrowband LEDs) in order to implement the spectral distributions of the illuminator corresponding to: the spectral reflectance of objects and the spectrum of white light with an adjustable color temperature and very high Color Fidelity Index and Gamut Index.
  Aims
  • define mathematical models that determine spectral power distributions of high-power LEDs depending on the electrical current and the temperature of the semiconductor junction,
  • develop a control algorithm for set of high-power LEDs in order to implement the given spectral power distributions of the illuminator,
  • set of multi-emitter tuneable LED illuminator,
  • selection of spectral power distribution of LED light to enhance the color contrast of the illuminated objects.
  Results

  The result of the project will be the methodology for adjusting (using the Monte Carlo method) spectral power distribution of a LED light source with set (adjustable) parameters:

  • the power (illuminance on the surface of the object),
  • the shape of the spectral power distribution corresponding to the spectral reflectance distribution of the illuminated object in order to enhance the contrast of its colors,
  • the correlated color temperature (CCT) in the range 2500-6500 Kelvins and very high Color Fidelity Index Rf > 95 and Gamut Index 95 < Rg < 105 in the case of required white light illumination.

Project manager: Assoc. Prof. Piotr Miluski, DSc, PhD, Eng.
Contractor: Faculty of Electrical Engineering,
Project number: 2020/37/B/ST7/03094
Source of funding: National Science Centre (Poland)
Name of the program: OPUS 19
Duration of the project: 01.02.2021 – 31.01.2025

Doping optical fibers with compounds of rare earth makes it possible to produce many active components, e.g. fiber amplifiers, radiation sources, and fiber lasers. The project aims is to develop a new design of multi-ring core silica fibers (MRC), enabling ultra-wideband emission in the spectral range that is safe for the eye (1.7-2.5 µm). The incorporation of one or more rare earth elements (RE, Rare Earth) allows the profiling of the luminescence spectrum through the phenomena of co-emission, exchange, and energy conversion in the energy structure of lanthanides (e.g. energy transfers, cross-relaxation). This makes it possible to significantly extend the luminescent properties of optical fibers to obtain radiation emission close to 2 μm. The possibility of obtaining new emission properties by optimizing the structure of the LMA (Large Mode Area) fiber and doping with lanthanides (Tm³⁺/Ho³⁺) (i.e. their spatial profile and concentration) will be investigated. An analysis of the influence of the refractive index profile, spatial doping profile (fiber cross-section), concentration, and the ratio will be carried out to obtain: high-quality optical beam at the output of a Large Mode Area optical fiber (LMA, NA<0.1), flattening of the emission profile in fiber structure as a result of the superposition of emission bands (Tm³⁺/Ho³⁺) and excitation systems using lasers with the continuous operation (CW) and ultrashort femtosecond pulses (fs). The development of new silica-based MRC optical fibers aims to obtain a high-quality beam (fundamental mode distribution) and a broadband emission spectrum. New aspects that will be investigated include MRI (Multi Ring Index) fiber structure design for mod field profiling, dispersion analysis, flattening of the luminescence spectrum profile in the 1.7-2.1 µm emission range (Tm³⁺/Ho³⁺) and its extension to 2.5 µm due to the effect of pulse broadening (fs) expected in the MRC Al/Tm³⁺ and Al/Tm³⁺/Ho³⁺ fibers. The implementation of the project provides for the simulation of the refractive index profile and the optical fiber structure to obtain a high-quality beam shape (mode field distribution). Optimization of the Rare Earth doping of the ring preform and the optical fiber will be carried out, analysis of the CW and fs pump scheme towards broadband emission in the eye-safe spectrum (especially above 2.1 μm). The simulations will cover the analysis of the mode field and profiling, the dispersion value through the arrangement of the multi-ring structure. The technology of the MCVD-CDT method (Modified Chemical Vapor Deposition – Chelate Doping Technique) will be used for the fabrication of optical fiber preforms, ensuring the possibility of controlling the structure of this type of doped structure. The key step in the development of the optical fiber structure will be the optical and structural characterization allowing the development and optimization of the parameters of the deposition process (MCVD-CDT) and the production of optical fibers. Process parameters will be developed to obtain the desired fiber structure. The produced MRC-LMA RE doped fibers (Al/Tm³⁺ and Al/Tm³⁺/Ho³⁺) will be characterized in terms of spectral characteristics and mode propagation. Various methods of continuous excitation and the use of ultra-short excitation pulses (fs) close to 1.9 µm will be used to optimize the shape of the optical spectrum (broadening, flattening). The obtained results of research on the structural and luminescent properties of silica optical fibers (MRC) will allow the construction of new sources of broadband, amplified spontaneous emission (ASE), and fiber lasers operating in the safe range for eyesight.

• Development of the new Multi Ring Core Large Mode Area (MRC-LMA) fibre constructions doped with Tm³⁺ and co-doped with Tm³⁺/Ho³⁺ ions.
• Optimisation of the optical fibre parameters: refractive index (RIP), rare-earth dopants profile, dispersion characteristic for broadband emission in the 1.7-2.1 µm spectral range.
• Optimisation of the pumping scheme of continuous wave (CW) and ultrashort femtosecond (fs) laser pulse excitation of MRC Al/Tm³⁺, Al/Tm³⁺/Ho³⁺ doped optical fibres for ultra – broadening and flattening of the emission spectrum in the MIR region up to 2.5 µm.

Project is pending.

Project manager: Prof. Tadeusz Kaczorek, DSc, PhD, Eng.
Contractor: Faculty of Electrical Engineering,
Project number: 2017/27/B/ST7/02443
Source of funding: National Science Centre (Poland)
Name of the program: OPUS 14
Duration of the project: 2018.06.12 – 2021.12.11

For more than four decades, there is a growing interest of engineers on fractional order derivatives and differences. Modern materials used in electrical engineering, mechanics, and other fields of technology require new mathematical operators to describe their properties that take into account, for example the memory of the past states in these materials. In addition, for many dynamic systems, the description using classical differential or difference equations of integer order does not provide sufficient precision – especially at high requirements for the quality of control of such objects. In recent years, many research centres in Poland and abroad have undertaken the studies on differential and difference calculus of arbitrary orders. Various definitions of fractional order derivatives have been formulated, the most popular are the derivatives of Caputo and Riemann-Liouville in the case of the continuous-time functions and the Grunwald-Letnikov definition of the fractional order for discrete-time functions. These definitions preserve many of the properties known from the differential and difference calculus of integer orders, although the properties such as differentiation of a constant function, chain rule, differentiation of product or quotient of two functions are not generally satisfied. In addition, there are many problems with the interpretation of the initial conditions for this type of definition. This has become the motivation for finding some new definitions of fractional order derivatives with properties that are compatible with the classical differential calculus. In recent years two interesting definitions of fractional order derivatives have been introduced: Caputo-Fabrizio and CFD (Conformable Fractional Derivative). The first one solved the problem of the singularity of the kernel of Riemann-Liouville and Caputo operators. CFD definition satisfies all the properties well-known for classical differential calculus including Leibniz rule, differentiation of product and quotient of two functions. This makes these two new operators a very useful tool for real dynamic objects modelling.

The aim of the project will be a comparative analysis of dynamic systems described by differential equations of fractional orders using different definitions of fractional order derivatives. The results of the analysis will be supported by numerical analysis and simulations in the Matlab computational environment. Next, after the verification of the usefulness of the obtained results, they will be confirmed by real objects measurements. The control algorithms developed in the project will be implemented in a microprocessor system and tested using the PXI computer.

• Comparative analysis of fractional order systems including systems with uncertain parameters for different type of fractional derivative: Caputo, Caputo-Fabrizio, Conformable
• Analysis of fractional order continuous-time nonlinear systems by the use of Lie algebra, extension of Popov, Kudrewicz theorems for fractional order nonlinear systems
• Synthesis of positive and standard fractional order systems including practical implementation and verification of chosen control techniques

• Three main research tasks have been conducted concurrently.
• During the study, linear algebra, matrix theory, linear matrix inequalities, and functional analysis have been used.
• Numerical computation has been done using Matlab/Simulink framework. PXI platform equipped in the data acquisition card supplied with LabView software has been used for measurements. Microprocessor starter board has been used in the identification process of supercapacitors parameters and implementation of control algorithms.
• Theoretical and practical outcomes of the project have been published in international journals, have been presented at conferences, and published as chapters in the monographs. In total, 46 papers have been published.
• This project greatly extends the outcomes of the previous project entitled “Descriptor nonlinear and linear systems of fractional orders” (NCN Opus 7) which was carried out by the same team of researchers.

Project manager: Assoc. Prof. Jacek Żmojda, DSc, PhD, Eng.
Contractor: Białystok University of Technology (leader)
Project number: 2019/35/O/ST5/03105
Source of funding: National Science Centre (Poland)
Name of the program: PRELUDIUM BIS

The research area of the project is in the field of photonic materials engineering. The scientific problem concerns the development of functional hybrid optical materials, such as transparent glass-ceramic optical fibers, which doped with lanthanide ions obtain unique luminescent properties for photonic applications. Generally, the glass-ceramic material consists of glass and suspended in amorphous volume nanocrystals doped with lanthanide ions. The controlled degree of crystallization is carried out in the process of heating materials at a specified temperature and at the right time of the experiment. Due to this, the glass-ceramic optical waveguide structures thus get better emission parameters (high quantum efficiency) compared to analogous amorphous structures, while maintaining the high optical quality. There are currently two main methods of producing nanocomposites. The first one, where optical fiber is made with classic drawing and then is annealing in this same way as in volume materials. This method is characterized by the multistep process, wherein each stage of the experiment the material is thermal treated (melting → bulk annealing → drawing fibers → heat-treatment). As a result, this process is very complex and controlling the size and density of nanocrystals is almost impossible. In addition, there are problems with their use in practical applications, because those optical fibers are brittle. Another way is the direct doping method of glass, which allows simplifying the process of nanocomposite material fabrication in a single step, where nanocrystals doped with lanthanum ions are added into supercooled liquid glass. As a result, hybrid material with high nanocrystals density is received, but also strong inhomogeneity, resulting from nanoparticle aggregation and partial degradation is observed. However, processing those materials into optical fibers leads to further degradation of the nanoparticles and thus decrease luminescent properties. Based on literature research and preliminary experiments the hypotheses that appropriate selection of the chemical composition of the glass, nucleators and the crystallization rate allows for obtaining transparent glass-ceramic optical fibers doped with lanthanides directly in the drawing process (one-step). A crucial research point is the development of a drawing-up fiber technique from supercooled liquid zone liquid with a high density of nucleating atoms while controlling the growth rate of nanocrystals. This is a new topic about the optimization of drawing-up of glass-ceramic optical fibers with a high volume of nanocrystals and controlled geometrical dimensions to preserve their functionality. Project results are a set of basic research that enables the development of GC optical fiber with high-quantum efficiency for high-power fiber lasers, functional light converters and a number of many photonic applications.