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Hybrid upconverting/paramagnetic Fe3O4/Gd2O3:Er3+, Yb3+, Mg2+, Nd3+ nanoparticles : synthesis, characterization and biological applications

Kamińska Izabela, Sobczak Kamil, Zhydachevskyy Yaroslav, Wojciechowski Tomasz, Minikayev Roman, Sikora-Dobrowolska Bożena, Lewińska Sabina, Chojnacki Michał, Fronc Krzysztof

Opto-Electronics Review

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2024

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Vol. 32, No. 2

art. no. e150182

EN

The goals of this work are to design and develop a technology for fabrication and study of multifunctional properties of core/shell nanoparticles (NPs) as magnetic/luminescent markers. The new hybrid core/shell Fe₃O₄/Gd₂O₃:1% Er³+, 18% Yb³+, 2.5% Mg²+, x% Nd³+ NPs doped with different concentrations of neodymium ions, where x = 0%, 0.5%, 0.75%, 1%, 2%, 4%, were synthesized by the co-precipitation method. The NPs were characterised using XRD, TEM, SEM, EDX, confocal microscopy and photoluminescence. Fe₃O₄ (core) consists of several 13 nm NPs. The core/shell NPs have sizes from 220 nm to 641 nm. In this latter case, the shell thicknesses were 72, 80, and 121 nm. The upconversion efficiency properties and magnetic properties of the hybrid NPs were investigated. In the core/shell NPs, the addition of Nd³+ quenches the luminescence. The magnetic response of core/shell samples is rather paramagnetic and does not differ significantly from that registered for the shell material alone. For Gd₂O₃:1% Er³+, 18% Yb³+ and Fe₃O₄/Gd₂O₃:1% Er³+, 18% Yb³+, 2.5% Mg²+, 0.5% Nd³+, at 300 K, the values of the magnetization registered at ~ 40 kOe are similar and equal to ~ 5.3 emu·g⁻¹. The survivability of the HeLa tumor cells with the presence of the core/shell NPs was investigated for 24 h. The NPs are non-toxic up to a concentration of 1000 μg·ml⁻¹ and penetrate cells in the process of endocytosis which has been confirmed by confocal microscope studies.

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Luminescence of hydrothermally fabricated PbF2:Er3+ particles and their application in bifacial silicon solar cells

Yang F, Wu C., Hao X, Chen Y., Lu J., Yang Sh.

Optica Applicata

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2014

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Vol. 44, nr 3

463--473

EN

We report the synthesis of PbF2:Er3+ particles using a hydrothermal method. The structure and upconversion emission properties of the products are investigated by scanning electron microscopy, X-ray diffractometer, Raman spectrophotometer and fluorescence spectrometry. An increase in Er3+ concentration in the crystals changes the PbF2 structure from a mixed phase to a cubic phase and decreases the grain size to nanoscale levels. Enhanced upconversion efficiency is achieved after annealing resulted from the formation of the cubic phase and the increase of grain size. The optimal Er3+ concentration is found to be 4% after annealing, and applied to the back of a bifacial silicon solar cell, maximum external quantum efficiencies of 0.38% and 0.79% are respectively obtained under 0.77 W/cm2 laser excitation (1560 nm) and AM1.5 + laser co-excitation.

3

Novel constructions of optical fibers doped with rare – earth ions

Dorosz J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 4

619--626

EN

In the paper the research on rare-earth doped and co-doped optical fibre conducted in the Laboratory of Optical Fiber Technology at the Bialystok University of Technology is presented. Novel active fibre constructions like multicore, helical-core and side detecting ribbon/core optical fibers were developed with a targeted focus into application. First construction i.e. multicore RE doped optical fibers enable supermode generation due to phase - locking of laser radiation achieved in a consequence of exchanging radiation between the cores during the laser action. In the paper a far - field pattern of 19 - core optical fiber-doped with Yb3+ ions, registered in the MOFPA system, showed centrally located peak of relatively high radiation intensity together with smaller side-lobes. Another new construction presented here is helical-core optical fibers with the helix pitch from several mm and the off-set ranging from 10 μm to 200 μm. The properties of helical-core optical fiber co-doped with Nd3+/Yb3+ were also discussed. In the field of sensor applications novel construction of a sidedetecting luminescent optical fiber for an UV sensor application has been presented. The developed optical fiber with an active core/ribbon, made of phosphate glass doped with 0.5 mol% Tb3+ ions, was used as a UV sensing element.

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Active glasses as the luminescent sources of radiation for sensor applications

Żmojda J., Dorosz D., Kochanowicz M., Dorosz J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 2

393--397

EN

The article presents physicochemical, thermal and spectroscopic properties of two different glass systems: TeO2-GeO2-PbO-PbF2- BaO-Nb2O5-LaF3 and SiO2-Al2O3-Sb2O3, co-doped with Yb3+/Tm3+ ions. Blue upconversion luminescence at a wavelength of 478 nm corresponding to the thulium 1G4 ⇥3H6 transition was observed under 976 nm pump radiation in both of the co-doped glasses. This indicated the existence of efficient Yb3+ ⇥ Tm3+ energy transfer via three-photon absorption mechanism. Thermal and optical results substantiate the claim for practical applicability of the manufactured glasses in design of optical fiber sources.

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Światłowód domieszkowany jonami Yb3+ i Tm3+

Dorosz D., Żmojda J., Kochanowicz M., Dorosz J.

Materiały Ceramiczne

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2010

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T. 62, nr 2

176-181

PL

W artykule przedstawiono wyniki badań nad dwupłaszczowym światłowodem domieszkowanym jonami Yb3+ i Tm3+. W wyniku pobudzania wytworzonego szkła, domieszkowanego jonami Yb3+/Tm3+, diodą laserową o długości fali λp = 976 nm uzyskano silne antystokesowskie pasmo luminescencji przy długości fali 477 nm odpowiadające przejściu 1G4→3H6 w strukturze energetycznej tulu. Ponadto przeprowadzono analizę wpływu koncentracji akceptora (Tm3+) przy stałej zawartości donora (Yb3+) na intensywności luminescencji. Dwupłaszczowy światłowód o rdzeniu ze szkła tellurowego domieszkowanego układem jonów Yb3+ i Tm3+ wytworzono metodą tyglową. W wyniku pobudzania optycznego promieniowaniem o długości fali λp = 976 nm badanego światłowodu zaobserwowano dodatkową linię emisji przy długości fali 351 nm odpowiadającą przejściu 1D2→3H6. W oparciu o model matematyczny kinetyki gęstości obsadzeń na poziomach metastabilnych jonu Tm3+ opisano powstały mechanizm konwersji wzbudzenia.

EN

Yb3+/Tm3+-doped tellurite-germanium glasses were fabricated and characterized. Strong blue emission at 477 nm corresponding to the 1G4→3H6 transition in thulium ions was investigated under the excitation with a 976 nm diode laser. The dependence of up-conversion emission intensity upon thulium ions concentration was analyzed. The most effective energy transfer Yb3+→Tm3+ occurs in the matrix when the molar ratio of Yb3+ to Tm3+ is 1:0.1. A crucible method was used to fabricate double-clad fibre with the active tellurite-germanium core. As a result of the excitation of fibre with the 976 nm diode laser, the ultraviolet emission at 351 nm (1D2→3H6) was measured. Based on the three- and four-photon absorption processes, the up-conversion mechanisms were evaluated by the proper rate of model equation.

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Szkła dla optoelektroniki

Reben M.

Szkło i Ceramika

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2009

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R. 60, nr 1

26-28

PL

W pracy opisano technologię otrzymywania szkło-ceramiki tlenkowo-fluorkowej produkowanej na bazie szkieł z układu SiO2-AI2O3-Na2O-LaF3. Dzięki równomiernemu rozmieszczeniu nanokrystalicznej fazy fluorku lantanu w matrycy szklistej, jak i możliwości przyjmowania do swej struktury pierwiastków ziem rzadkich otrzymana szkło-ceramika znajduje zastosowanie w optoelektronice jako wzmacniacze optyczne czy konwertory częstotliwości.

EN

The paper presents new glass-ceramics from the SiO2-AI2O3-Na2O-LaF3 system which were obtained as a potential materials for optoelectronics. After a thermal treatment close to the crystallization temperature it is possible to obtain a glass-ceramic, in which fluoride nanocrystals are embedded in a primarily oxide glass matrix. Oxyfluoride glass-ceramic combine the particular optical properties of rare earth ions in fluoride hosts with the elaboration and manipulation advantages of oxide glasses.

7

Fluorescence labelling

Goldys E.M., Drozdowicz-Tomsia K., Zhu G., Yu H., Yu H., Jinjun S., Motlan M., Godlewski M.

Optica Applicata

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2006

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Vol. 36, nr 2-3

217-224

EN

Fluorescence labelling has become a technique of increasing importance in modern biotechnology which is increasingly underpinned by advances in materials science. In this paper we describe our contributions to this area. In order to expand the understanding of in vivo fluorescence labelling we carried out the staining of membrane-based structures in effectively secreting Trichoderma reesei using the fluorescent dye FM 4-64 and their confocal microscopy studies. We also describe the observation of efficient fluorescence upconversion in Sm-doped Gd2O3 nanopowders synthesised by the spray pyrolysis method. This result indicates the potential for Sm-doped Gd2O3 to perform as a fluorescent label excited in red, yellow and green and emitting in blue. Finally, we report a simple approach for synthesizing water-soluble CdS nanoparticles by using ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA) as a stabilizer.

8

LaF3 nanocrystals as a host for Er3+ in oxyfluoride glass

Środa M., Reben M., Kwaśny M., Wacławska I.

Optica Applicata

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2005

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Vol. 35, nr 4

851-858

EN

The paper presents new glass-ceramics as a material for up-conversion luminescence. Formation of the LaF3 nanocrystals have been obtained as a low phonon host for rare earth active ions in oxide glassy matrix. The thermal conditions of LaF3 nanocrystallization in the glass from the SiO2-Al2O3-Na2O-LaF3 system have been presented. Transmittance and luminescence properties as a function of heat treatment have been investigated. The effect of incoming of Er3+ in LaF3 crystals has been shown on the luminescence properties. AFM results have confirmed the growth of nano-scale crystals.

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Investigation and modelling of rare-earth activated waveguide structures

Woliński W., Malinowski M., Mossakowska-Wyszyńska A., Piramidowicz R., Szczepański P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2005

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Vol. 53, nr 2

97-102

EN

In this paper the overview of the recent study on the rare-earth activated waveguides performed in the Optoelectronic Department of IMiO is presented. We reported on the development of rare earth-doped fluorozirconate (ZBLAN) glass fibers that allow a construction of a new family of visible and ultraviolet fiber lasers pumped by upconversion. Especially the performance of holmium devices is presented. The properties of laser planar waveguides obtained by the LPE process and the growth conditions of rare earths doped YAG layers are presented. In this paper we present also the theoretical study of the nonlinear operation of planar waveguide laser, as an example the micro disk Nd:YAG structure is discussed. We derived an approximate formula which relates the small signal gain in the Nd:YAG active medium and the laser characteristics, obtained for whispering-gallery modes and radial modes, to the output power and real parameters of the laser structure

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Infrared-to-visible upconversion in erbium fluoride (ZBLAN:Er³⁺) optical fiber: competition between the parasitic 850-nm fluorescence and the green laser emission at 544 nm

Kaczmarek F., Karolczak J.

Opto-Electronics Review

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2004

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Vol. 12, No. 2

247-248

EN

The role of 850-nm fluorescence, amplification, and laser emission in ZBLAN:Er³⁺ optical fiber was first investigated by Whitley et al. [1,2] and Allain et al. [3]. In the case of a green upconversion fiber laser at 544 nm, the 850-nm fluorescence is a parasitic component, so it should be minimized or eliminated. Two pumping wavelengths are usually applied to excite the green upconversion laser: 970 nm or 800 nm. It has been already observed that 800-nm pumping favours, to some extend, the 850-parasitic emission, and the 970-nm one makes this emission negligible [1–3]. We have studied the role of 800-nm pumping in more detail and observed a dependence of the pumping wavelength ~800 nm on the intensity of the 850-nm parasitic fluorescence.