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1

The determination of the carriers recombination parameters based on the HOT HgCdTe current-voltage characteristics

Manyk Tetiana, Rutkowski Jarosław, Madejczyk Paweł, Gawron Waldemar, Martyniuk Piotr

Opto-Electronics Review

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2022

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Vol. 30, No. 2

art. no. e141596

EN

A theoretical analysis of the mid-wavelength infrared range detectors based on the HgCdTe materials for high operating temperatures is presented. Numerical calculations were compared with the experimental data for HgCdTe heterostructures grown by the MOCVD on the GaAs substrates. Theoretical modelling was performed by the commercial platform SimuAPSYS (Crosslight). SimuAPSYS fully supports numerical simulations and helps understand the mechanisms occurring in the detector structures. Theoretical estimates were compared with the dark current density experimental data at the selected characteristic temperatures: 230 K and 300 K. The proper agreement between theoretical and experimental data was reached by changing Auger-1 and Auger-7 recombination rates and Shockley-Read-Hall carrier lifetime. The level of the match was confirmed by a theoretical evaluation of the current responsivity and zero-bias dynamic resistance area product (R0A) of the tested detectors.

2

Implementing evolutionary algorithm into training single-layer artificial neural network in classification task

Płaczek S.

Information Systems in Management

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2016

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Vol. 5, No. 3

377--388

EN

The article proposes implementing a modified version of genetic algorithm in a neural network, what in literature is known as “evolutionary algorithm” or “evolutionary programming”. An Evolutionary Algorithm is a probabilistic algorithm that works in a set of weight variability of neurons and seeks the optimal value solution within a population of individuals, avoiding the local maximum. For chromosomes the real value variables and matrix structure are proposed to a single-layer neural network. Particular emphasis is put on mutation and crossover algorithms. What is also important in both genetic and evolutionary algorithms is the selection process. In the calculation example, the implementation of theoretical considerations to a classification task is demonstrated.

3

Struktura pułapkowa izolatorów ceramicznych sieci energetycznych średnich napięć

Mandowski A., Mandowska E., Sobota R., Kornatka M.

Przegląd Elektrotechniczny

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2015

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R. 91, nr 9

121-124

PL

O własnościach elektrycznych izolatora w znacznym stopniu decyduje struktura energetyczna defektów sieci krystalicznej. Defekty sieci powodują powstanie zlokalizowanych poziomów elektronowych wewnątrz przerwy energetycznej izolatora. W zależności od wartości energii aktywacji poziomy te mogą pełnić rolę pułapek nośników ładunku lub centrów rekombinacji. Strukturę pułapkową izolatorów ceramicznych sieci energetycznych średnich napięć badano przy użyciu termoluminescencji. W zakresie temperatur 300 – 600 K widmo termoluminescencji pokazuje obecność co najmniej kilku pułapek i centrów rekombinacji, których parametry zależą od rodzaju badanego izolatora.

EN

Electrical properties of an insulator are largely determined by the energy structure of the crystal lattice defects. Lattice defects give rise to localized electronic levels inside the energy gap of the insulator. These energy levels may act as charge carrier traps or recombination centers depending on the value of the activation energy. The trap structure of the ceramic insulators of medium voltage power networks were studied using thermoluminescence. In the temperature range of 300 – 600 K thermoluminescence glow curve shows the presence of at least a few traps and recombination centers, whose parameters depend on the type of insulator under study.

4

Modelowanie zjawiska spadku sprawności dla dużych gęstości prądów w diodach elektroluminescencyjnych z azotków

Cegielski T.

Prace Instytutu Elektrotechniki

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2012

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Z. 255

7-18

PL

Pomimo rozwoju, który nastąpił w technologii wytwarzania białych elektroluminescencyjnych źródeł światła, w urządzeniach tych ciągle istotną ograniczającą rolę pełni zjawisko spadku sprawności generacji światła dla dużych gęstości prądu. Ponadto wciąż nierozpoznane dostatecznie są jego fizyczne podstawy. W referacie przedstawiono możliwe modele opisujące ten efekt, opierając się na dyskutowanych w literaturze hipotetycznych przyczynach: różnych rodzajach rekombinacji Augera, efektach termicznych, występowaniu silnych pól elektrycznych i asymetrii występowania nośników, itp. Poznanie potencjalnych powodów zjawiska spadku efektywności pozwoli na dalszy rozwój źródeł światła opartych na elektroluminescencji. Przełoży to się na niższy koszt uzyskania zamienników tradycyjnych źródeł światła i większe ich rozpowszechnienie, co w istotny sposób może ograniczyć wzrost światowego zużycia energii.

EN

Despite the development that occurred in the technology of white Light-Emitting Diodes, this devices are still limited by the phenomenon of the efficiency droop that occurs in light generation for large current densities. Moreover, its physical basis is still not sufficiently recognized. The paper presents possible models describing this effect, based on the hypothetical reasons discussed in the literature: different types of Auger recombination, thermal effects, the presence of strong electric fields and the occurrence of the asymmetry of carriers, etc. Knowing the potential reasons for the droop phenomenon will allow the further development of Solid State Light sources. This leads to lower cost retrofits or replacements of traditional light sources and greater their market penetration, which may significantly reduce global energy consumption increase.

5

Detection of recombinant mitochondrial genomes: Implications for the mechanism of mtDNA inheritance in mussel Mytilus

Filipowicz M., Burzyński A., Wenne R.

Environmental Biotechnology

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2008

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Vol. 4, No. 2

54-59

EN

Recombination plays a fundamental role in the creation of biodiversity. It is the mechanism inducing formation of rearrangements within the genomes which, beside mutations, are the major source of genetic variation. In the process of recombination a single or double DNA strand is broken and rejoined with unassociated DNA fragments. There are several types of recombination: homologous recombination, sitespecific recombination and transposition. Within mitochondrial genomes, inter- and intra-molecular recombination can occur. Except for intramolecular recombination of mtDNA, the other types of recombination always result in the creation of mosaic genomes. However, in the natural populations mtDNA recombination is detected extremely rarely. It is caused by the clonal inheritance of mitochondrial genomes and consequential lack of sufficient divergence between parental mitochondrial molecules. Mussels of the genus Mytilus possess two types of mitochondrial genomes inherited from males and females, respectively, and their mode of mtDNA inheritance is called doubly uniparental inheritance (DUI). The presence of two highly diverged parental molecules gives the opportunity for detection of recombinant variants. This feature of Mytilus mtDNA can be broadly exploited in the search for and characteristics of recombinant sequences. Apart from the high level of sequence divergence, fusion of mitochondria and appropriate enzymatic toolkit are principal requirements for the occurrence of recombination. The majority of phylogenetic and demographic analysis based on mtDNA assumes the lack of recombination. If this assumption turned out to be erroneous, previous analyses would be weakened. Recombination is associated with DUI abnormalities, e.g. masculinization of mitochondrial genomes. It may even lead to the breakdown of DUI system resulting in the new, unidentified mode of mtDNA inheritance in mussel Mytilus that might be regulated by stochastic events.

6

Organic light emitting devices

Godlewski J., Obarowska M.

Opto-Electronics Review

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2007

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Vol. 15, No. 4

179-183

EN

The purpose of this paper is to provide general information about basic physical processes involved in organic electroluminescence and to present the main parameters and advantages of organic light emitting devices (OLEDs).

7

An impact of physical phenomena on admittances of partially-depleted SOI MOSFETs

Tomaszewski D., Łukasiak L., Gibki J., Jakubowski A.

Journal of Telecommunications and Information Technology

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2001

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nr 1

57-60

EN

An influence of the selected physical phenomena: impact ionization in silicon and time variation of internal electric field distribution in partially-depleted (PD) SOI MOSFETs on several C-V characteristics of these devices is presented. The role of avalanche multiplication in the so-called "pinch-off" region is discussed in a more detailed way. The analysis is done using a numerical solver of drift-diffusion equations in silicon devices and using an analytical model of the PD SOI MOSFETs. The calculations results exhibit the significance of proper modelling of the phenomena in the floating body area of these devices.

8

Influence of protons on oxide compounds applied in optoelectronic devices

Kaczmarek S. M., Wojtkowska J., Moroz Z., Kisielewski J.

Biuletyn Wojskowej Akademii Technicznej

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2000

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Vol. 49, nr 2

99-113

EN

Changes in optical properties of some oxide compounds (YAG, YAG: Nd³⁺, YAG: Ce³⁺, YAG: Ce³⁺, Mg²⁺, YAG: Cr³⁺, YAG: Cr⁴⁺, SrLaGa₃O₇: Dy³⁺, SrLaGa₃O₇: Cr³⁺, SrGdGa₃O₇:Cr³⁺ and LiNbO₃: Cu²⁺) induced by 21 MeV proton irradiation were studied. In the optical absorption spectra lines which belong to optically active dopants (like Ce³⁺, Cr³⁺, Fe³⁺) and F-type color centers are seen. Influence of proton irradiation on such centers is observed. It seems to be attributed to the ionization and/or recombination of definite centers. Moreover, for relatively high proton fluencies, Frenkel defects are probably created.

PL

Badano zmiany właściwości optycznych materiałów tlenkowych (YAG, YAG: Nd²⁺, YAG: Ce²⁺, YAG: Ce²⁺, Mg²⁺, YAG: Cr²⁺, YAG: Cr ⁴⁺ , SrLaGa₃O₇: Dy²⁺, SrLaGa₃O₇: Cr²⁺, SrGdGa₃O₇:Cr²⁺ oraz LiNbO₃: Cu²⁺) indukowane przez wiązkę protonów o energii 21MeV z cyklotronu. Wśród linii absorpcyjnych obserwowano linie należące do domieszek aktywnych (jak Ce²⁺, Cr²⁺, Fe²⁺) oraz do centrów barwnych typu F. Oddziaływanie protonów na te centra wydaje się być związane z jonizacją i/lub rekombinacją powyższych centrów. Ponadto, dla względnie wysokich strumieni protonów (1014 protonów/cm²), obserwuje się powstawanie defektów Frenkla.

9

A model of dynamics of mutation, genetic drift and recombination in DNA-repeat genetic loci

Polańska J., Kimmel M.

Archives of Control Sciences

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1999

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Vol. 9, no. 1/2

143-157

EN

We present a model of genetic dynamics of a population of chromosomes, involving mutation, drift and recombination at a pair of repeat-DNA sequences. Such sequences, known as microsatellites and VNTR's, are commonly used as markers in studies in forensics, molecular evolution and gene mapping. The model we use has the form of a time-continuous Markov chain. It is further transformed to the form of a differential equation for probability generating functions. This description allows to follow dynamics with a variety of initial conditions. It allows, among other, to model the so called linkage disequilibrium, i.e. the state in which, due to processes like newly arisen mutation, selection, or population admixture, there exists a dependence between alleles at two loci. Recombination gradually dissolves the linkage disequilibrium, with additional contributions from drift and mutation. The model, in its complete form, is rather involved, since it includes all possible occurrences related to three genetic forces: mutation, genetic drift and recombination. However, we find explicit solutions to special cases which allow to understand the dynamics of dissolution of linkage disequilibrium. Other special cases of the model include the previously known relationships involving mutations and genetic drift. Also, we derive equations for the moments of the random variables present in the model. The moments can be used to define distance measures between distributions of alleles.