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1

Enhanced catalytic activity of zeolitic imidazolate frameworks (ZIF-8) polyelectrolyte complex composites membranes by laser etching

Yu Ting, Kitiyanan Boonyarach, Dubas Stephan Thierry

Materials Science Poland

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2024

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Vol. 42, No. 1

52--61

EN

The effect of laser etching on the surface properties of composite polyelectrolyte complex (PEC) based membranes as mixed matrix membranes was studied. The PECs were prepared by the stoichiometric mixing of cationic PDDA (poly(diallyl dimethyl ammonium chloride)) and anionic PSS (poly(sodium 4-styrene sulfonate)) as polyelectrolytes with various contents of ZIF-8 as filler. Composite membranes usually display improved bulk properties depending on the nature of the filler, but the surface properties are often dictated by the matrix covering the surface. The PEC composite membranes were then subjected to laser etching, resulting in the enhanced exposure of embedded ZIF-8 particles within the PEC structure in an attempt to improve the surface properties of the composite membrane. The crystal structure, morphology, and distribution of zinc at the PECs surface, before and after laser etching, were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS), respectively. In order to evaluate the improvement of the surface properties of the laser-etched membranes, a model experiment involving a catalytic reaction was chosen. The pristine and laser treated surfaces were tested for their catalytic activity for the transesterification of triglycerides present in soybean oil with methanol at a temperature of 150°C. Interestingly, the laser-etched PECs displayed substantially enhanced activity compared to the original composite PEC membranes as a result of surface erosion. These results could be interesting for the future development of composite membranes with improved surface properties where the filler needs to expose the surface of the membranes.

2

Technologie cięcia w produkcji kanałów wentylacyjnych z blach powlekanych

Michalski Dariusz, Kurp Piotr, Kroner Andrzej

Stal, Metale & Nowe Technologie

|

2023

|

nr 3-4

60--69

PL

W niniejszym artykule autorzy analizują technologie cięcia blach i taśm stalowych ocynkowanych wg PN-EN 10346:2015-09 [1] w gatunku DX51DZ275-M-A-C [2], o wydatku ocynku 275 g/m2. Wykorzystuje się je do produkcji różnego rodzaju kształtek wentylacyjnych prostokątnych i kanałów. Materiały o grubości w zakresie od 0,6 do 1,5 mm stosowane do produkcji muszą spełniać wymagania normy PN-89/H-92125.

EN

In this article, the authors analyse the technologies of cutting galvanized steel sheets and strips according to PN-EN 10346:2015-09 [1] in the grade DX51DZ275-M-A-C [2], with the galvanizing coating of 275 g/m2. They are used for the production of various types of rectangular ventilation fittings and ducts. Materials with a thickness in the range from 0.6 to 1.5 mm used for production must meet the requirements of the PN-89/H-92125 standard. The process of cutting, i.e. the loss of material consistency, consists in mechanical or thermal impact on the material until it is cut or burned through its entire thickness.

3

Ultra-szybka transmisja światłowodowa na potrzeby centrów danych

Turkiewicz Jarosław

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2023

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nr 4

24--28

PL

Wzrost ilości informacji przesyłanych w ramach centrów danych i superkomputerów stymuluje rozwój i wykorzystanie dopasowanych do ich potrzeb oraz wymagań technik transmisyjnych. W referacie zostaną zaprezentowane techniki transmisji danych o wysokich przepływnościach wykorzystujące lasery VCSEL i światłowody wielomodowe.

EN

Growth of data transmitted within the data centers and supercomputers stimulates development of novel data transmission techniques adjusted to the data center needs. In the paper, ultra-high speed transmission techniques utilizing VCSEL laser and multimode fibres are presented.

4

Development of a Solid, Low-Smoke Rocket Propellant : Smoke Generation Intensity Tests Using a Laser and Photodiode Setup

Woźniak Przemysław, Kindracki Jan, Wacko Krzysztof, Gołofit Tomasz, Chmielarek Michał, Cieślak Katarzyna, Kozłowska Sylwia, Maksimowski Paweł, Mężyk Łukasz, Kołodziej Maciej, Zdybał Dominik

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

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2023

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Vol. 14, Nr 3 (53)

41--58

EN

The work completed and discussed in this paper was to determine the level of smoke generation intensity in a selection of solid rocket propellants developed to minimise the level of generated smoke. This is an important issue for the application of the developed low-smoke propellant in, for example, the sustainer motor of a rocket missile. Reduced smoke generation levels can help to significantly reduce the feasibility of enemy detecting rocket munition launch sites. The authors of this paper developed a test stand that quantified the smoke generation intensity in rocket propellants. The test stand setup, based on the scatter of a laser beam by smoke, measured the smoke generation intensity, including during the operation of a rocket motor. A rocket micromotor was used along with a test chamber to measure the intensity of the smoke generated. It was located directly behind the motor exhaust and provided three laser- photodiode measurement channels. Tests of the smoke generated during the combustion of black powder and a standard mixture of HTPB and AP at a ratio of 20:80 provided reference baselines for the smoke generation intensity tests on the developed rocket propellants. The authors determined the smoke generation intensity of the propellants based on ADN, HTPB, and GAP with various additives. The results produced made it possible to compare the tested materials and select the most preferable materials as measured by their low smoke generation intensity.

PL

Przeprowadzone prace miały na celu określenie poziomu intensywności dymienia wybranych stałych, rakietowych materiałów pędnych, opracowanych przy założeniu minimalizacji generowanego przez nie dymu. Stanowi to istotne zagadnienie w kontekście zastosowania opracowanego materiału pędnego o zmniejszonym dymieniu, np. w silniku marszowym pocisku rakietowego. Ograniczenie wytwarzania dymu może znacząco zmniejszyć możliwości wykrycia miejsca startu środków bojowych przez przeciwnika. Autorzy artykułu opracowali stanowisko badawcze umożliwiające otrzymanie wskazań intensywności dymienia rakietowych materiałów pędnych. Przygotowany system, oparty na rozpraszaniu wiązki światła laserowego w dymie, umożliwia pomiar intensywności dymienia m.in. w warunkach pracy silnika rakietowego. Zastosowano mikrosilnik rakietowy wraz z komorą badawczą układu pomiaru dymienia, umieszczoną tuż za wylotem z mikrosilnika, wyposażoną w trzy tory pomiarowe laser- fotodioda. Pomiary generowanego dymu podczas spalania prochu czarnego oraz standardowej mieszaniny HTPB z AP w stosunku 20-80 stanowiły poziomy odniesienia do porównania intensywności dymienia opracowanych materiałów pędnych. Autorzy określili intensywność dymienia materiałów pędnych opartych na zastosowaniu ADN, HTPB lub GAP oraz różnych dodatków. Otrzymane rezultaty pozwalają na porównywanie przebadanych materiałów oraz wyselekcjonowanie najlepszych pod kątem niskiej intensywności dymienia.

5

Narodowe Laboratorium Fotoniki i Technologii Kwantowych - NLPQT

Fita Piotr, Suster Mihai

Postępy Fizyki

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2023

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T. 74, z. 1

14--18

PL

Narodowe Laboratorium Fotoniki i Technologii Kwantowych - NLPQT to projekt inwestycyjny, którego celem jest budowa infrastruktury pozwalającej na prowadzenie badań i prac badawczo-rozwojowych w zakresie technologii wykorzystujących światło i zjawiska kwantowe. Infrastruktura jest budowana przez zespoły badawcze pracujące w siedmiu polskich jednostkach naukowych. Po zakończeniu inwestycji będzie ona dostępna zarówno dla pracowników naukowych z innych ośrodków, jak i dla zainteresowanych przedsiębiorców działających w obszarze nowych technologii. W artykule przedstawiamy założenia dotyczące budowanej infrastruktury i opisujemy przykładowe stanowiska badawcze, których konstrukcja została już prawie ukończona.

EN

The National Laboratory of Photonics and Quantum Technologies - NLPQT is an investment project aimed at building an infrastructure that will allow research and development work in the field of technologies that use light and quantum phenomena. The infrastructure is built by research teams working in seven Polish research institutions. After the investment is completed, it will be available both to researchers from other research centers and to interested entrepreneurs operating in the field of new technologies. In the article, we present the assumptions regarding the NLPQT infrastructure and describe example research stations, the construction of which has already been almost completed.

6

Capabilities of Thomson parabola spectrometer in various laser-plasma- and laser-fusion-related experiments

Tchórz Przemysław, Szymański Maciej, Rosiński Marcin, Chodukowski Tomasz, Borodziuk Stefan

Nukleonika

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2023

|

Vol. 68, No. 1

29--36

EN

The Thomson parabola spectrometer (TPS) [1] is a well-known, universal diagnostic tool that is widely used in laser plasma experiments to measure the parameters of accelerated ions. In contrast to other popular ion diagnostics, such as semiconductor detectors or ion collectors, the TPS is not greatly affected by electromagnetic pulses generated during high-power laser interaction with matter and can be tuned to acquire data in various energy ranges of accelerated ions, depending on the goal of the experiment. Despite the many advantages of this diagnostic device, processing the collected data is a diffi cult task and requires a lot of caution during interpretation of gathered results. In this work, we introduce the basic principles of operation and data analysis based on the numerical tool created specifi cally for the TPS designed at the Institute of Plasma Physics and Laser Microfusion, present a range of data obtained during various recent experiments in which our TPS was used, and highlight the diffi culties in data analysis depending on the purpose of the experiment and the experimental setup.

7

Reduction of optical noise in near-infrared range laser hygrometry

Stacewicz Tadeusz, Winkowski Mateusz, Kuk Natalia

Metrology and Measurement Systems

|

2023

|

Vol. 30, nr 1

169--181

EN

A contactless laser hygrometer based on light absorption by H2O molecules at 1392.5 nm is described. However, measurement results can be affected by optical noise when applied to an atmospheric tunnel or glass cuvette. The noises (occurring in the form of periodic fringes in the recorded spectrum) come from unexpected interference of the light beams reflected from surfaces of the windows or other optical elements. The method of their suppression is described in this article. It is based on wavelength modulation and signal averaging over the fringes period. Also, an experiment confirming the usefulness of this method is described here.

8

Photo-thermal Decomposition of HNS Surface by 532 nm Laser Irradiation : Spectral and Quantitative Analysis using In-Situ XPS- Quadrupole MS Technique

Sun Yi, Xu Tao, Shui Min

Central European Journal of Energetic Materials

|

2023

|

Vol. 20, no. 1

36--49

EN

A novel approach for studying the photo-thermal decomposition of HNS (2,2’,4,4’,6,6’-hexanitrostilbene) at 532 nm induced by a 10-nanosecond (ns) laser pulse is described. In this method, in-situ X-ray photoelectron spectrometer (XPS) - laser-quadrupole mass spectrometer on-line equipment was designed. New peaks at binding energies of 399.7 eV in the N 1s XPS spectrum and 288.6 eV in the C 1s spectrum showed that nitro-nitrite isomerization with subsequent release of NO occurs in the laser-induced decomposition of HNS. A new peak at 30 m/z in the mass spectrum is also associated with the mechanism of the nitro-nitrite isomerization of the HNS molecule, with subsequent release of NO. Quantum chemistry calculation results are in good agreement with the experimental results. We attribute this laser-induced decomposition as a photo-thermal decomposition for the high temperature rise due to the laser irradiation.

9

Analiza wybranych technologii cięcia blach powlekanych stosowanych do produkcji kanałów wentylacyjnych

Michalski Dariusz, Kurp Piotr, Kroner Andrzej

Stal, Metale & Nowe Technologie

|

2022

|

nr 5-6

80--87

PL

W niniejszym artykule autorzy analizują technologie cięcia blach i taśm stalowych ocynkowanych wg PN-EN 10346:2015-09 [1] w gatunku DX51DZ275-M-A-C [2], o wydatku ocynku 275 g/m2. Wykorzystuje się je do produkcji różnego rodzaju kształtek wentylacyjnych prostokątnych i kanałów. Materiały o grubości w zakresie od 0,6 do 1,5 mm stosowane do produkcji muszą spełniać wymagania normy PN- -89/H-92125. Proces cięcia, czyli utraty spójności materiału, polega na mechanicznym lub cieplnym oddziaływaniu na materiał do momentu jego przecięcia lub przepalenia na całej jego grubości.

EN

In this article, the authors analyse the technologies of cutting galvanized steel sheets and strips according to PN-EN 10346:2015-09 [1] in the grade DX51DZ275-M-A-C [2], with the galvanizing coating of 275 g/m2. They are used for the production of various types of rectangular ventilation fittings and ducts. Materials with a thickness in the range from 0.6 to 1.5 mm used for production must meet the requirements of the PN-89/H-92125 standard. The process of cutting, i.e. the loss of material consistency, consists in mechanical or thermal impact on the material until it is cut or burned through its entire thickness.

10

Drukowanie cyfrowe – elektrofotografia

Khadzhynova Svitlana, Jakucewicz Stefan

Przegląd Papierniczy

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2022

|

R. 78, nr 1

28--33

PL

Celem artykułu było przedstawienie historii rozwoju drukowania cyfrowego. Zaprezentowano etapy rozwoju drukowania elektrofotograficznego – od analogowej techniki kserografii, wynalezionej przez Chestera Carlsona w 1938 r., do współczesnych cyfrowych maszyn elektrofotograficznych. Opisano również okoliczności pojawienia się systemów DTP, które były kamieniem milowym na drodze rozwoju drukowania cyfrowego.

EN

The aim of this article was to prezent the history of the digital printing development history. The development stages of the electrophotographic printing from analog xerography, invented by Chester Carlson in 1938, to contemporary digital electrophotographic machines. The circumstances of DTP systems appearance are described as well. These systems are the milestone on the way to digital printing development.

11

Badanie własności grubowarstwowego kontaktu srebro-węglik krzemu modyfikowanego wiązką laserową

Woźny Janusz, Kubiak Andrzej

Przegląd Elektrotechniczny

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2022

|

R. 98, nr 1

169--172

PL

W pracy zaprezentowana jest metoda uzyskiwania kontaktów omowych do węglika krzemu z wykorzystaniem srebrowego kleju przewodzącego oraz lasera modyfikującego obszar kontaktu. Metoda nie wymaga przeprowadzania procesu wygrzewania całej struktury. Może ona znaleźć zastosowanie w pracach laboratoryjnych nad SiC wymagających szybkiego wytworzenia kontaktów omowych do struktur z SiC.

EN

The paper presents a method of obtaining ohmic contacts to silicon carbide with the use of a silver conductive adhesive and a laser beam modifying the contact area. The method does not require the whole structure annealing process. It can be used in laboratory work on SiC requiring rapid creation of ohmic contacts to SiC structures.

12

Experimental studies of the possibility of laser processing as a cleaner method of achieving a surface with good adhesion

Ciecińska Barbara

Production Engineering Archives

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2022

|

Vol. 28, Iss. 3

233--240

EN

In manufacturing processes many technological operations are designed, in which the adhesive properties of the treated surface are very important. These are processes related to application of any coating on the surface, such as gluing, painting, varnishing and others. Durability of coatings depends on proper preparation of the surface to which they are going to be applied. Conventional methods, such as grinding, sandblasting with subsequent washing and degreasing, as well as galvanic treatment applied to e.g. aluminium alloys - require the use of not only specific equipment but also chemical substances. They often lead to a significant burden on the environment due to their harmful properties. In an experimental study, attention was drawn to the significant environmental aspects of such a technological process and work was carried out to demonstrate whether it is possible to eliminate toxic and hazardous substances and to create good adhesion conditions by laser processing. To this purpose, samples were made out of two representative materials: X6Cr17 steel and AW-2024 aluminium alloy, abrasive surface treatment or in a galvanic bath and then washed, degreased and dried. Laser surface treatment without the use of additional chemicals was proposed as an environmentally cleaner technology. Surface roughness and adhesion of the test polymer coating were measured for comparative evaluation of the applied treatment methods. Obtained results were discussed in terms of the possibility of eliminating harmful influences and implementing laser treatment as a cleaner technology in the production of components requiring coating.

13

Fabrication and amplified spontaneous emission behavior of FAPbBr3 perovskite quantum dots in solid polymer rods

Khan M. Naziruddin, Almohammedi Abdullah

Materials Science Poland

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2022

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Vol. 40, No. 1

84--100

EN

Formamidinium lead tribromide (FAPbBr3) perovskite quantum dot (PQ-Dot) solution was incorporated in a polymer sol, which was used to fabricate solid nanocomposite rods and disks. The solid nanocomposite samples were studied by different characterization techniques. The absorption, emission, and excitation spectra of the PQ-Dot in the solid rods/disks were quite significant as compared to the spectra of the PQ-Dot solution. Scanning electron microscopy (SEM) was used to inspect the structural morphology of the PQ-Dot in the solid environment. The PQ-Dot particles were evidently present in the solid matrix and were confirmed by the SEM images and energy dispersive X-ray spectroscopy (EDX) spectra. The size of the PQ-Dots was examined by transmission electron microscopy (TEM). The majority of the particles were about 3–8 nm in size. The spontaneous and stimulated emission profiles of the solid composite rods/disks were studied using pumping energy ranging from 2 μJ to 18 μJ from a high-power picosecond neodymium-doped yttrium aluminum garnet (Nd:YAG) tunable laser system. The observed emission signal was quite significant. The emission peak of the PQ-Dot solution had a slight change when it was included in the solid matrix. Amplified spontaneous emission (ASE) behavior was obtained from the PQ-Dot composite rod. The ASE peaks were quite steady at different levels of excitation energy. ASE was achieved at low threshold energy. The composite rod with ASE behavior indicates that it is a promising composite material that can be used to achieve lasing in the future. The ASE obtained from the composite rods/disks may improve to achieve lasing if a high concentration of PQ-Dot solution is used in the matrix.

14

Technika laserowa

Romaniuk Ryszard

Elektronika : konstrukcje, technologie, zastosowania

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2022

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Vol. 63, Nr 10

12--19

PL

Technika laserowa obejmuje badania, konstrukcję i zastosowania laserów, urządzeń i systemów laserowych. Obecne zastosowania laserów są bardzo szerokie i obejmują np. badania podstawowe i techniczne, technikę satelitarną, astronomię, telekomunikację, technikę komputerową, biologię i medycynę, ochronę środowiska, obróbkę materiałów, przemysł, technikę wojskową i wiele innych obszarów. Wraz z rozwojem badań i konstrukcji, generacje funkcjonalnych laserów zmieniają się np. pod względem efektywności, kosztów, wygody zastosowania, itp. Na przykład klasyczne generacje laserów stosowane w technikach spawalniczych są zastępowane elastycznymi rozwiązaniami wykorzystującymi lasery światłowodowe. Dalszy znaczny postęp obserwuje się w obszarze teorii i budowy laserów dla fotoniki zintegrowanej i nanofotoniki. Nanofotonika kwantowa jest potencjalnie jedną z podstaw nowej kwantowej generacji technik informacyjnych, komputingu kwantowego w wersji fotonicznej, fotonicznej metrologii kwantowej, fotonicznych czujników kwantowych, kwantowych metod obrazowania, znacznie dokładniejszych metod pomiaru czasu i częstotliwości, itp. W dniach 19-23 września br. w Karpaczu odbyło się 13 Krajowe Sympozjum Techniki Laserowej zorganizowane przez uczonych fotonicznych i laserowych z Politechniki Wrocławskiej. Sympozjum zgromadziło ponad 150 osób z całego kraju i podsumowało znakomite krajowe osiągnięcia techniki laserowej w okresie ostatnich czterech lat od spotkania.

EN

Laser technology includes research, construction and application of lasers, laser devices and systems. Current laser applications are very broad and include, for example, basic and technical research, satellite technology, astronomy, telecommunications, computer technology, biology and medicine, environmental protection, material processing, industry, military technology and many other areas. With the development of research and construction, the generations of functional lasers change, for example in terms of efficiency, cost, convenience of use, etc. For example, classic generations of lasers used in welding techniques are being replaced by flexible solutions using fiber lasers. Further significant progress is observed in the area of the theory and construction of lasers for integrated photonics and nanophotonics. Quantum nanophotonics is potentially one of the foundations of a new generation of quantum information techniques, photonic quantum computing, photonic quantum metrology, photonic quantum sensors, quantum imaging methods, much more accurate time and frequency measurement methods, etc. The 13th National Symposium on Laser Technology was organized in Karpacz on 19-23 September 2022, by photonic and laser scientists from the Wrocław University of Technology. The symposium gathered over 100 people from all over the country and summarized the outstanding national achievements of laser technology in the last four years from the previous meeting.

15

Geometry Characterization of AISI 430 Stainless Steel Microstructuring Using Laser

Moldovan Edit R., Concheso Doria Carlos, Ocaña Moreno Jose Luis, Baltes Liana Sanda, Stanciu Elena Manuela, Croitoru Catalin, Pascu Alexandru, Tierean Mircea Horia

Archives of Metallurgy and Materials

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2022

|

Vol. 67, iss. 2

645--652

EN

Laser-generated surface patterns provide the means for local mechanical interlocking between the joined materials, tunes the wettability of surfaces that come in contact, and generally are the main factor for bonding strength enhancement, especially between dissimilar materials. This paper presents the influence of different patterning overlays generated with a pulsed laser on the surface of stainless-steel sheets. For all experiments, an overlapping degree of 90% has been chosen between three different patterns, while the engraving speed, pulse frequency and number of passes have varied. The textured surfaces’ morphology was assessed through optical microscopy, and the roughness of the surfaces was correlated with the corresponding experimental parameters. The results have indicated promising insights for joining stainless steel to plastic materials, which is otherwise difficult to assess through usual welding techniques.

16

Nowe zastosowanie szkła. Geometria tunelików misternie wydrążonych w szkle, pozwalająca przesyłać światło bez rozpraszania

Szkło i Ceramika

|

2021

|

R. 72, nr 1

71--72

17

Analiza wybranych technologii cięcia blach powlekanych stosowanych do produkcji kanałów wentylacyjnych

Michalski Dariusz, Kurp Piotr, Kroner Andrzej

Stal, Metale & Nowe Technologie

|

2021

|

nr 11-12

46--56

PL

W niniejszym artykule autorzy analizują technologie cięcia blach i taśm stalowych ocynkowanych wg PN-EN 10346:2015-09 [1] w gatunku DX51DZ275-M-A-C [2], o wydatku ocynku 275 g/m2. Wykorzystuje się je do produkcji różnego rodzaju kształtek wentylacyjnych prostokątnych i kanałów. Materiały o grubości w zakresie od 0,6 do 1,5 mm stosowane do produkcji muszą spełniać wymagania normy PN- -89/H-92125. Proces cięcia, czyli utraty spójności materiału, polega na mechanicznym lub cieplnym oddziaływaniu na materiał do momentu jego przecięcia lub przepalenia na całej jego grubości.

EN

In this article, the authors analyse the technologies of cutting galvanized steel sheets and strips according to PN-EN 10346:2015-09 [1] in the grade DX51DZ275-M-A-C [2], with the galvanizing coating of 275 g/m2. They are used for the production of various types of rectangular ventilation fittings and ducts. Materials with a thickness in the range from 0.6 to 1.5 mm used for production must meet the requirements of the PN-89/H-92125 standard. The process of cutting, i.e. the loss of material consistency, consists in mechanical or thermal impact on the material until it is cut or burned through its entire thickness.

18

Optymalizacja warunków przecinania laserowego polipropylenu i polipropylenu z dodatkiem talku

Cienka Agnieszka Edyta, Ciecińska Barbara

Physics for Economy

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2021

|

Vol. 4

17-27

PL

Przecinanie laserem materiałów wymaga wykonania prób obróbki i wyboru najkorzystniejszego wariantu z punktu widzenia przyjętych kryteriów oceny jakości procesu. W pracy przedstawiono przykład procesu przygotowawczego, z którego wynika, że przecinanie polipropylenu i polipropylenu z talkiem o grubości 5 mm nie jest łatwą obróbką. Wykorzystano laser CO2 i różnicując wykorzystaną moc lasera oraz prędkość przesuwu wiązki względem materiału uzyskano przecięcia materiału o zróżnicowanej jakości. Zaproponowano także kryteria wyboru najlepszego wariantu obróbki. Stwierdzono, że dodatek talku do polipropylenu może być czynnikiem ułatwiającym wykonanie cięcia laserem tego tworzywa.

19

Optimization of laser cutting conditions of polypropylene and polypropylene with talc

Cienka Agnieszka Edyta, Ciecińska Barbara

Physics for Economy

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2021

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Vol. 4

5-15

EN

Laser cutting of materials requires the execution of processing tests and the selection of the most favourable variant from the point of view of the adopted criteria of process quality assessment. This paper presents the example of a preparatory process, which shows that cutting polypropylene and polypropylene with 5 mm thick talc is not an easy process of material handling. A CO2 laser was used and by varying the utilized power from the laser and the beam speed relative to the material, cuts of varying quality were obtained. Criteria were also proposed for the selection of the best processing variant. It was concluded that the addition of talc to polypropylene can be a factor facilitating laser cutting of this material.

20

Investigation of a tunable and switchable multi-wavelength bidirectional Brillouin-erbium fiber ring laser

Wang F., Yuan R. Y.

Optica Applicata

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2021

|

Vol. 51, nr 3

375--389

EN

A multi-wavelength bidirectional Brillouin-erbium fiber ring laser with switchable Brillouin frequency spacing (BFS) is proposed and experimentally demonstrated. In the presented Brillouin-erbium ring laser, including an optical amplifier and a highly nonlinear fiber, and without any optical isolator, due to Rayleigh scattering, stimulated Brillouin scattering, and cascaded four-wave mixing initiated successively by the Brillouin pump (BP) light, the odd- and even-order Stokes lines are generated and circulate in the opposite direction in the ring cavity. The BP light and Stokes-induced Rayleigh backscattering light also simultaneously circulate in the ring cavity. Only by adjusting BP power, the gain competition between Brillouin based Stokes and cavity modes’ oscillation can be controlled, the laser output can be conveniently switched between single BFS and odd- or even-order double BFS. In addition, under the certain BP power conditions, the proposed multi-wavelength Brillouin-erbium fiber laser also can realize switchable odd- or even-order Stokes generation and Stokes generation with single BFS, with an increasing wavelength number in turn, only by simply adjusting pump power of the erbium-doped fiber amplifier. Stability and wavelength tunability of the proposed multi-wavelength bidirectional Brillouin-erbium fiber ring laser are also investigated, respectively.