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1

Peculiarities in optical response of hybrid-barrier GaSb/InAs/AlSb resonant tunneling diode structure

Dyksik M., Motyka M., Rygała M., Pfenning A., Hartmann F., Weih R., Worschech L., Höfling S., Sęk G.

Optica Applicata

|

2021

|

Vol. 51, nr 2

171--180

EN

We present comprehensive investigation of the optical properties of hybrid-barrier GaSb-based resonant tunneling structures, containing a bulk-like GaInAsSb absorption layer and two asymmetric type II GaSb/InAs/AlSb quantum wells. Methods of optical spectroscopy by means of Fourier-transformed photoluminescence and photoreflectance are employed to probe optical transitions in this complex multilayer system. Based on the comparison between the absorption-like and emission-like spectra (also in function of temperature) confronted with band structure calculations four main transitions could be resolved and identified. For one of them, there has been observed unusually strong linear polarization dependence never reported in structures of that kind. It has been interpreted as related to a transition at the GaSb/GaInAsSb interface, for which various scenarios causing the polarization selectivity are discussed.

2

Struktury tunelowe studnia kwantowa-kropki kwantowe jako ośrodek czynny laserów telekomunikacyjnych

Rudno-Rudziński W.

Przegląd Elektrotechniczny

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2017

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R. 93, nr 8

20--23

PL

Kropki kwantowe mają wiele zalet jako laserowy materiał aktywny, jednak wykorzystanie ich w laserach telekomunikacyjnych wymaga uzyskania bardzo szybkiej modulacji emisji, trudnej do osiągnięcia w układzie czysto kropkowym, z powodu znacznej populacji gorących nośników. Możliwym rozwiązaniem jest zastosowanie hybrydowych struktur tunelowych, w których studnia kwantowa, oddzielona cienką barierą od warstwy kropek, służy jako rezerwuar nośników dostarczanych bezpośrednio do stanu podstawowego. W artykule zaprezentowane są różne układy materiałowe, w których zrealizowany został schemat tunelowy, umożliwiające uzyskanie emisji w zakresie podczerwieni telekomunikacyjnej. Uzupełniajace się techniki spektroskopii optycznej wykorzystane zostały do zbadania własności struktur pod kątem ich zastosowań w laserach. Przedstawione są również wyzwania na drodze do uzyskania lasera wykorzystującego szybkie i wydajne tunelowanie ze studni do kropek.

EN

Quantum dots (QD) offer many advantages as active material for lasers, however in order to take advantage of them in telecom lasers it is necessary to assure high modulation speed, difficult to achieve in purely QD system due to high population of hot carriers. One of feasible solutions is to use hybrid structures, where a quantum well, separated by a thin barrier from QD layer, serves as a reservoir of carriers supplied directly to the ground state. The article presents several material systems used to realise tunnel injection scheme, enabling emission in the telecom infrared range. Complementary optical spectroscopic techniques are employed to investigate the properties of structures in view of laser applications. There are also presented challenges on the way to obtain a laser based on fast and efficient tunneling.

3

Ag₈SnSe₆ argyrodite synthesis and optical properties

Semkiv I., Ilchuk H., Pawlowski B., Kusnezh V.

Opto-Electronics Review

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2017

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Vol. 25, No. 1

37--40

EN

The Ag₈SnSe₆ argyrodite compound was synthesized by the direct melting of the elementary Ag, Sn and Se high purity grade stoichiometric mixture in a sealed silica ampoule. The prepared polycrystalline material was characterized by the X-ray diffraction (XRD), visible (VIS) and near-infrared (NIR) reflection and photoluminescence (PL) spectroscopy. XRD showed that the Ag₈SnSe₆ crystallizes in orthorhombic structure, Pmn2₁ space group with lattice parameters: ɑ = 7.89052(6) Ǻ, b = 7.78976(6) Ǻ, c = 11.02717(8) Ǻ. Photo-luminescence spectra of the Ag₈SnSe₆ polycrystalline wafer show two bands at 1675 nm and 1460 nm. Absorption edge position estimated from optical reflectance spectra is located in the 14131540 nm wavelength range.

4

Research on interactions of plasma streams with CFC targets in the Rod Plasma Injector facility

Zaloga D. R., Kwiatkowski R., Skladnik-Sadowska E., Sadowski M. J., Nowakowska-Langier K.

Nukleonika

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2016

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Vol. 61, No. 2

179--183

EN

This paper present results of optical spectroscopy studies of interactions of intense plasma streams with a solid target made of carbon fibre composite (CFC). The experiments were carried out within the Rod Plasma Injector (RPI) IBIS facility. The optical measurements were performed first for a freely propagating plasma stream in order to determine the optimal operational parameters of this facility. Optical emission spectra (OES) were recorded for different operational modes of the RPI IBIS device, and spectral lines were identified originating from the working gas (deuterium) as well as some lines from the electrode material (molybdenum). Subsequently, optical measurements of plasma interacting with the CFC target were performed. In the optical spectra recorded with the irradiated CFC samples, in addition to deuterium and molybdenum lines, many carbon lines, which enabled to estimate erosion of the investigated targets, were recorded. In order to study changes in the irradiated CFC samples, their surfaces were analysed (before and after several plasma discharges) by means of scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) techniques. The analysis of the obtained SEM images showed that the plasma irradiation induces noticeable changes in the surface morphology, for example vaporisation of some carbon fi bres and formation of microcracks. The obtained EDS images showed that upon the irradiated target surface, some impurity ions are also deposited, particularly molybdenum ions from the applied electrodes.

5

Rudowicz Cz., Karbowiak M.

Nukleonika

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2015

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Vol. 60, No. 3, part 1

377--383

EN

The interface between optical spectroscopy, electron magnetic resonance (EMR), and magnetism of transition ions forms the intricate web of interrelated notions. Major notions are the physical Hamiltonians, which include the crystal field (CF) (or equivalently ligand field (LF)) Hamiltonians, and the effective spin Hamiltonians (SH), which include the zero-fi eld splitting (ZFS) Hamiltonians as well as to a certain extent also the notion of magnetic anisotropy (MA). Survey of recent literature has revealed that this interface, denoted CF (LF) ↔ SH (ZFS), has become dangerously entangled over the years. The same notion is referred to by three names that are not synonymous: CF (LF), SH (ZFS), and MA. In view of the strong need for systematization of nomenclature aimed at bringing order to the multitude of different Hamiltonians and the associated quantities, we have embarked on this systematization. In this article, we do an overview of our efforts aimed at providing a deeper understanding of the major intricacies occurring at the CF (LF) ↔ SH (ZFS) interface with the focus on the EMR-related problems for transition ions.

6

Miniaturowe helowe źródła wirującej plazmy - nowe, użyteczne narzędzie w spektroskopii analitycznej

Giersz J., Jankowski K., Ramsza A., Reszke E.

Analityka : nauka i praktyka

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2015

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nr 3

14--21

PL

Ze względu na swoje unikalne właściwości wirujące plazmy mogą być zastosowane w wielu technikach spektroskopii optycznej i spektrometrii mas. Interesujące wydaje się łączenie źródeł wirującej plazmy z technikami oznaczania różnego rodzaju gazowych form analitów.

7

Detection and measurement of the optical signals emitted by the partial discharges

Fedorowicz P.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

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2014

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z. 70

17-18

EN

This paper presents possibilities of detection and measurement of the optical signals emitted by the partial discharges in the infrared, visible and ultraviolet spectrum using optical spectroscopy, thermographic and ultraviolet cameras as well as photographic techniques.

8

Fotoluminescencyjne badania wpływu temperatury na własności emisyjne periodycznych nanostruktur fotonicznych

Urbańczyk D. M., Wójcik-Jedlińska A., Kosiel K., Bugajski M.

Elektronika : konstrukcje, technologie, zastosowania

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2014

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Vol. 55, nr 11

57-59

PL

Praca prezentuje zastosowanie wyzoskorozdzielczej spektroskopii fotoluminescencyjnej do analizy wpływu temperatury na własności emisyjne periodycznych nanostruktur półprzewodnikowych. Przedmiotem badań były supersieci Al0.45GaAs0.55/GaAs zaprojektowane jako obszar czynny laserów kaskadowych. Struktury zostały osadzone metodą epitaksji z wiązek molekularnych na podłożu GaAs. Wykonano pomiary widm fotoluminescencji obszaru supersieci w różnych warunkach termicznych, w zakresie temperatury od 5 do 65°C. Na podstawie zmian spektralnego położenia pików fotoluminescencji wyznaczono parametr przesunięcia temperaturowego wynoszący ok. 0,3 nm/K.

EN

The paper presents photoluminescence study of the temperature effect on the optical properties of semiconductor periodic nanostructures. The research was performed on Al0.45GaAs0.55/GaAs superlattices grown by molecular beam epitaxy on GaAs substrate. The structures have been designed as an active region of quantum cascade lasers. The temperature dependences were determined based on the results of high resolution photoluminescence measurements carried out at different temperature of values ranging from 5 to 65°C. The obtained temperature offset of the emission spectra was ~0.3 nm/K.

9

Optical emission spectra of Zn and Bi in pulsed magnetron plasma

Ziaja J., Ozimek M.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 7

324--326

EN

This study aimed at determining the relations between technological parameters of sputtering process - power discharge, the targetsubstrate distance, working gas pressure and the chemical composition of pulsed magnetron plasma by means of optical spectrophotometry. Planar 0.90Zn-0.10Bi target was sputtered in Ar, O2 and in the atmosphere of the both gases mixture. Optical emission spectra were measured in 200800 nm wavelength range.

PL

Za pomocą spektroskopii optycznej określono korelacje pomiędzy parametrami procesu rozpylania - moc wyładowania, odległość target-podłoże, ciśnienie gazu, a składem chemicznym plazmy magnetronowego wyładowania jarzeniowego. W badaniach zastosowano stop 0,90Zn-0,10Bi. Target rozpylano w atmosferze argonu (Ar), tlenu (O2) oraz mieszaninie obu tych gazów. Widma emisyjne rejestrowano w zakresie długości fal od 200-800 nm.

10

Rozwój nauk optycznych w kraju

Romaniuk R. S.

Elektronika : konstrukcje, technologie, zastosowania

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2013

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Vol. 54, nr 8

93-98

PL

Środowisko naukowe i techniczne optyki, fotoniki i optoelektroniki jest zgrupowane w kraju w kilku organizacjach. Są to Polskie Stowarzyszenie Fotoniczne (PSP), Polski Komitet Optoelektroniki SEP, Sekcja Fotoniki KEiT PAN, Klub Laserowy na WAT oraz Sekcja Optyki PTF. Każde z tych środowisk posiada nieco odmienną specyfikę. PSP wydaje kwartalnik Photonics Letters of Poland, stymuluje współpracę międzynarodową i organizuje konferencje w czasie targów przemysłowych fotoniki. PKOpto organizuje dyplomowe konkursy dydaktyczne z dziedziny fotoniki. KEiT PAN patronuje krajowym konferencjom dziedziny techniki laserowej, światłowodów oraz zastosowaniom fotoniki. SO-PTF podjęła się ostatnio organizacji cyklicznej „Polskiej Konferencji Optycznej". Trzecia edycja tej konferencji PKO'2013 odbyła się w Sandomierzu w dniach 30 czerwca – 4 lipca br. Konferencja obejmuje następującą tematykę naukową i techniczną: optyka kwantowa i nieliniowa; fizyka, optyka i technologia laserów oraz innych źródeł promieniowania spójnego; optoelektronika; optyczne układy zintegrowane, optyka światłowodowa; optyka medyczna; optyka instrumentalna; spektroskopia optyczna; metrologia optyczna; nowe materiały optyczne; zastosowania optyki, oraz dydaktyka optyki. W artykule dokonano przeglądu wybranych prac konferencji PKO'2013, reprezentujących różne naukowe optyczne ośrodki krajowe.

EN

Research and technical communities for optics, photonics and optoelectronics is grouped in this country in several organizations and institutions. These are: Photonics Society of Poland (PSP), Polish Committee of Optoelectronics of SEP, Photonics Section of KEiT PAN, Laser Club at WAT and Optics Section of PTF. Each of these communities keeps slightly different specificity. PSP publishes a quarterly Journal Photonics Letters of Poland, stimulates international cooperation and organizes conferences during Industrial Fairs on Innovativeness. PKOpto SEP organizes didactic diploma competitions in optoelectronics. KEiT PAN takes patronage over national conferences in laser technology, optical fiber technology and photonics applications. SO-PTF has recently taken a decision to organize a cyclic event "Polish Optical Conference". The third edition of this conference PKO'2013 was held in Sandomierz on 30.06-04.07.2013. The conference scientific and technical topics include: quantum and nonlinear optics, photon physics, optic and technology of lasers and other sources of coherent radiation, optoelectronics, optical integrated circuits, optical fibers, medical optics, instrumental optics, optical spectroscopy, optical metrology, new optical materials, applications of optics, teaching in optics. This paper reviews chosen works presented during the III Polish Optical Conference, representing the research efforts at different national institutions.

11

Spektroskopia emisyjna plazmy zasilanej impulsowo w trakcie magnetronowego rozpylania stopu Zn i Bi

Ziaja J., Ozimek M.

Prace Instytutu Elektrotechniki

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2012

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Z. 259

51--52

PL

Za pomocą spektroskopii optycznej określono korelacje pomiędzy technologicznymi parametrami procesu rozpylania – moc wydzielona na materiale rozpylanym, odległość target – podłoże, ciśnienie gazu roboczego, a składem chemicznym magnetronowej plazmy zasilanej impulsowo. W badaniach zastosowano metaliczny stop 0,90Zn-0,10Bi, o średnicy 50 mm. Target rozpylano w atmosferze argonu (Ar), tlenu (O2) oraz w atmosferze będącej mieszaną tych gazów. W mieszaninie ciśnienie parcjalne tlenu zmieniano w zakresie 0 < pO2 / p(O2 + Ar) < 1. Optyczne widma emisyjne zmierzono w zakresie długości fal od 200-800 nm. Stwierdzono, że dla różnych warunków pracy magnetronu widma emisyjne różnią się od standardowych. Wykazano, iż wartość intensywności Ibi oraz IZn wzrasta wraz ze wzrostem mocy dostarczanej do materiału rozpylanego i maleje w funkcji odległości od niego. Intensywności są również funkcją ciśnienia parcjalnego tlenu. Zmieniając stosunek IZn/IBi można w sposób kontrolowany otrzymywać warstwy o zadanym składzie chemicznym, co jest bardzo istotnym elementem z technologicznego punktu widzenia.

EN

This study aimed at determining the relations between technological parameters of sputtering process – power dissipated in the target, the distance target – substrate, working gas pressure and the chemical composition of pulsed magnetron plasma by means of optical spectrophotometry. Planar 0.90Zn – 0.10Bi target with a diameter of 50 mm was sputtered in Ar, O2 and in the atmosphere of both gases mixture. In the mixture of both gases the partial pressure of oxygen was changed in the range 0 < pO2 / p(O2 + Ar) < 1. Optical emission spectra were measured in 200 – 800 nm wavelength range. The intensity of characteristic optical lines of bismuth and zinc for selected wavelengths (λBi = 306.77 nm and λZn = 636.23 nm) was studied. It was stated that for various conditions of magnetron operation the emission spectra are different from the standard ones. It was shown that the intensity of IBi and IZn lines increases along with the increase of power supplied to the target and decreases in the distance function from it. It was also proven that the intensity of characteristic optical lines of bismuth and zinc depends on the oxygen partial pressure. The relative lines intensities IBi and IZn are a function decreasing along with the increase in oxygen concentration.

12

Optical emission spectroscopy of plasma produced from tungsten target irradiated within RPI - IBIS facility

Skladnik-Sadowska E., Malinowski K., Sadowski M. J., Nowakowska-Langier K., Ladygina M. S., Garkusha I. E.

Nukleonika

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2012

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Vol. 57, No. 2

193-196

EN

The paper presents recent research on characteristics of deuterium plasma streams generated within an RPI-IBIS (multi-rod plasma injector) facility, and optical spectra of plasma produced during the interaction of these streams with a tungsten target placed at a distance of 20 cm from the electrode outlets. Distinct WI- and WII-lines were recorded and the noticeable erosion of the W-target was observed for shots delivering more than 4 J/cm2 on the target surface.

13

Application of high resolution microscopy and optical spectroscopy for study of phase separation in phosphorus- and fluorine-containing sodium borosilicate glasses

Antropova T. V., Drozdova I., Kukhtevich I., Evstrapov A., Esikova N.

Optica Applicata

|

2010

|

Vol. 40, nr 2

293--304

EN

The kinetics of phase separation in glass-forming Na2O–B2O3–SiO2–P2O5–|F| system and structure parameters of the two-phase glasses have been investigated by transmission electron microscopy (TEM) and optical spectroscopy methods. The TEM images were analyzed with the help of specially designed software for the purpose of determination of the relative volume and size of the phases. An influence of duration of a glass heat treatment on the parameters of their structure was investigated at a temperature of 550 °C which is necessary for prompting a two-network structure and is most frequently used for manufacturing porous glasses. The time of glass heat treatment necessary for achieving phase equilibrium was established. A deviation of the phase inhomogeneity growth rate from theoretical one was determined. It was revealed that a certain third phase, the composition of which can include ?-quartz, is formed in glass during the heat treatment. Fluorescence of the two-phase glass which has been subjected to heat treatment for a long time can be caused by the presence of this phase.

14

Spektroskopia w podczerwieni w analizie tworzyw polimerowych : charakterystyka metody i różne obszary zastosowań

Kamińska-Bach G.

Przetwórstwo Tworzyw

|

2008

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[R.] 14, nr 3

70-74

PL

W artykule przybliżono metodę spektroskopii w podczerwieni. Opisano poszczególne rodzaje metod spektralnych stosowanych w badaniach laboratoryjnych. Podano przykłady zastosowań tej techniki w analizie tworzyw polimerowych, min. w próbach identyfikacji tworzyw i związków a także w monitorowaniu procesu starzenia materiałów polimerowych pod wpływem promieniowania UV, temperatury (destrukcja wiązań i powstawanie nowych wiązań o odmiennym charakterze). Omówione zostały podstawowe elementy aparatury badawczej.

EN

IR spectroscopy method was described in the article. Particular kinds of spectral methods used for laboratory tests were presented. The examples of application of this technique for plastics analysis, including identification of plastics and chemical compounds as well as monitoring of ageing process of plastic materials under the influence of UV radiation and temperature (destruction of chemical bonds and creation of new bonds of different character) were presented. Basic elements of testing equipment were described.

15

Aggregation of Some TTF Derivatives and Their Adducts with C60

Olejniczak I., Kędziora P., Bogucki A., Połomska M., Graja M.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 11

1473-1482

EN

Spectral investigations of selected tetrathiafulvalene-derived donor molecules (TTFs) and the fullerene-derived adducts with these donors linked to them were performed. The main attention has been devoted to studies of possible intermolecular interactions, in particular to aggregation processes in these materials.

16

New Bis-Linked Tetrathiafulvalenes (TTFs) to [60] Fullerene : Spectral Investigations

Olejniczak I., Graja A., Bogucki A., Gorgues A., Kreher D., Cariou M.

Polish Journal of Chemistry

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2002

|

Vol. 76 / nr 1

95-102

EN

Extended spectral investigations of several new bis-linked tetrathiafulvalenes (TTFs) to [60]fullerene were performed. From VIS-NIR-IR spectra it was stated, that charge redistribution on C60 and TTFs moieties in the adducts occurs after their formation. This redistribution depends not only on the nature of a substituent but also on the number of bounded donors. Vibrational features of the polyadducts were also analyzed.

17

Optical properties of fluoroindate glasses doped with rare earth ions.

Gabryś-Pisarska J., Żelechower M., Pisarski W.A., Gołąb S., Bałuka M., Ryba-Romanowski W.

Optica Applicata

|

2000

|

Vol. 30, nr 4

517-528

EN

Multicomponent indium based fluoride glass singly doped with europium, terbium, holmium and thulium has been investigated using methods of optical spectroscopy. Owing to low energy of phonons available in the glass matrix, the luminescent levels of rare earth ions are depopulated mainly by radiative transitions and nonradiative ion-ion interaction. The latter mechanism has been found to govern the relaxation dynamics of the /sup 5/D/sub 2/, /sup 5/D/sub 1/ levels of europium, the /sup 5/D/sub 3/ level of terbium, the /sup 5/S/sub 2/ level of holmium and the /sup 2/D/sub 5/, /sup 1/G/sub 4/ and /sup 3/H/sub 4/ levels of thulium when the activator concentration amounts to several mol%.

18

Linear and nonlinear optical spectroscopy of CdS nanoparticles in Nafion membranes

Bourdin E., Henari F.Z., Blau W.J., Kelly J.M.

Journal of Telecommunications and Information Technology

|

2000

|

nr 1-2

29-36

EN

CdS nanoparticles embedded in Nafion membranes were studied by a variety of optical spectroscopic methods. Quantum confinement was achieved (particle mean diameter of 40 A) and the growth was found to follow a linear temporal kinetic law. Discrete energy levels were observable, even at room temperature. They could be attributed to light hole and heavy hole IS and 2S transitions. The experimental results are in good agreement with theoretical calculations of light hole and heavy hole masses in the cases of cubic CdS. An enhancement of the nonlinear susceptibility chi(3) at the quantized exciton energy levels was observed. The clusters were found to be photo-unstable, with a diffusion-limited growth rate due to Ostwald ripening.