Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "M.B." wg kryterium: Autor


Tytuł:
ZnO Nanopowders by a Microwave Hydrothermal Method - Influence of the Precursor Type on Grain Sizes
Autorzy:
Wolska, E.
Witkowski, B. S.
Godlewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/2048108.pdf
Data publikacji:
2011-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.-n
61.43.Gt
81.07.Wx
78.55.Et
Opis:
Two series of ZnO nanopowders obtained by a microwave hydrothermal method are examined. We used two different zinc precursors (zinc chloride (ZnCl$\text{}_{2}$) and zinc nitrate hexahydrate (N$\text{}_{2}$O$\text{}_{6}$Zn·6H$\text{}_{2}$O)). Both types of nanopowders show a bright emission in a visible light, including the band edge emission, which indicates their good crystallographic quality. Results of scanning electron microscopy, photo- and cathodoluminescence investigations are presented.
Źródło:
Acta Physica Polonica A; 2011, 119, 5; 683-685
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Annealing on Optical Properties of ZnO Nanorods Obtained by the Microwave-Assisted Hydrothermal Process
Autorzy:
Materska, P.
Witkowski, B.
Godlewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1185899.pdf
Data publikacji:
2016-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.-m
61.46.-w
61.72.Cc
Opis:
Optical properties of ZnO nanorods (of different sizes, grown on two different substrates) are investigated. Nanorods were grown using microwave-assisted hydrothermal process on gallium nitride or silicon substrate. To initiate nanorods growth on a silicon substrate ZnO nucleation layer was used. ZnO nanoseeds were deposited by atomic layer deposition. For GaN substrate an epitaxial relation was observed. For both substrates nanorods show a hexagonal structure, expected for wurtzite ZnO. Results of nanorods annealing are discussed.
Źródło:
Acta Physica Polonica A; 2016, 130, 5; 1202-1204
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact Ionization Driven Chaotic Photoluminescence Oscillations in Ga$\text{}_{0.47}$In$\text{}_{0.53}$As
Autorzy:
Godlewski, M.
Fronc, K.
Gajewska, M.
Chen, W.M.
Monemar, B.
Powiązania:
https://bibliotekanauki.pl/articles/1888119.pdf
Data publikacji:
1991-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.35.+z
72.70.+m
76.90.+d
Opis:
A new application of the Optically Detected Cyclotron Resonance (ODCR) is presented. We report impact ionization studies of bound exciton: (BE) and shallow donor related recombination processes in Ga$\text{}_{0.47}$In$\text{}_{0.53}$As. An appearance of chaotic oscillations in photoluminescence (PL) intensity is observed under condition of impact ionization of deeper donors.
Źródło:
Acta Physica Polonica A; 1991, 80, 2; 271-274
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optically Detected Magnetic Resonance Studies of Te-Related Shallow Donors in Al$\text{}_{x}$Ga$\text{}_{1-x}$As
Autorzy:
Godlewski, M.
Fronc, K.
Chen, W. M.
Monemar, B.
Powiązania:
https://bibliotekanauki.pl/articles/1890838.pdf
Data publikacji:
1991-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.55.Eq
72.20.Jv
76.70.Hb
78.55.Cr
Opis:
The first studies of the Optically Detected Magnetic Resonance (ODMR) of Te-doped (x = 0.42) are presented. The ODMR data indicate an efficient energy transfer between epilayer and GaAs substrate.
Źródło:
Acta Physica Polonica A; 1991, 80, 3; 341-344
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-ray Absorption Fine Structure Investigation of the Low Temperature Grown ZnCoO Films
Autorzy:
Wolska, A.
Klepka, M.
Witkowski, B.
Witkowski, M.
Guziewicz, E.
Godlewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1431568.pdf
Data publikacji:
2012-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.70.Dm
75.50.Pp
68.55.-a
Opis:
ZnO based diluted magnetic semiconductors are intensively investigated for possible spintronic applications. In the present work we investigate the ZnCoO layers grown at low temperature by atomic layer deposition. The local atomic structure of a series of layers with different Co concentration is investigated by the X-ray absorption fine structure measurements. Two groups of ZnCoO layers are investigated - the ones with an uniform Co distribution and highly nonuniform films. For uniform samples we observe that a majority of Co atoms is built into the ZnO matrix substituting the Zn atoms. In contrast, for the nonuniform samples, metallic Co inclusions are also observed. These results are in strong correlation with the magnetic properties of the films studied separately. Samples with the uniform Co distribution (Co substitutes Zn in ZnO) are paramagnetic, whereas the nonuniform ones show a ferromagnetic response.
Źródło:
Acta Physica Polonica A; 2012, 121, 4; 883-887
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ZnCoO Films by Atomic Layer Deposition - Influence of a Growth Temperature οn Uniformity of Cobalt Distribution
Autorzy:
Łukasiewicz, M.
Witkowski, B.
Godlewski, M.
Guziewicz, E.
Sawicki, M.
Paszkowicz, W.
Łusakowska, E.
Jakieła, R.
Krajewski, T.
Kowalik, I.
Kowalski, B.
Powiązania:
https://bibliotekanauki.pl/articles/1791350.pdf
Data publikacji:
2009-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.55.Ln
68.55.Nq
78.66.Hf
81.15.Kk
Opis:
We report on the structural, electrical and magnetic properties of ZnCoO thin films grown by atomic layer deposition method using reactive organic precursors of zinc and cobalt. As a zinc precursor we applied either dimethylzinc or diethylzinc and cobalt(II) acetyloacetonate as a cobalt precursor. The use of these precursors allowed us the significant reduction of a growth temperature to 300°C and below, which proved to be very important for the growth of uniform films of ZnCoO. Structural, electrical and magnetic properties of the obtained ZnCoO layers will be discussed based on the results of secondary ion mass spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, atomic force microscopy, Hall effect and SQUID investigations.
Źródło:
Acta Physica Polonica A; 2009, 116, 5; 921-923
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cathodoluminescence Profiling for Checking Uniformity of ZnO and ZnCoO Thin Films
Autorzy:
Witkowski, B. S.
Łukasiewicz, M. I.
Wolska, E. A.
Kopalko, K.
Kowalski, B. J.
Guziewicz, E.
Godlewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/2048105.pdf
Data publikacji:
2011-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.15.Gh
78.30.Fs
78.60.Hk
Opis:
We employ scanning electron microscopy and cathodoluminescence for evaluation of uniformity of ZnCoO films obtained by the atomic layer deposition. Cathodoluminescence quenching by Co ions allows us to detect (regions of weaker light emission) Co accumulations, with the resolution limited by diffusion length of secondary carriers.
Źródło:
Acta Physica Polonica A; 2011, 119, 5; 675-677
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ZnO dla fotowoltaiki
ZnO for Photovoltaics
Autorzy:
Godlewski, M.
Łuka, G.
Pietruszka, R.
Wachnicki, Ł.
Witkowski, B.
Powiązania:
https://bibliotekanauki.pl/articles/159146.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Elektrotechniki
Tematy:
fotowoltaika
tlenek cynku
photovoltaics
zinc oxide
Opis:
Mimo znaczącej redukcji kosztów paneli fotowoltaicznych (PV), cena energii wytwarzanej przez baterie słoneczne ciągle jest za wysoka. Możliwe są dwie strategie rozwiązania tej sytuacji – (a) podniesienie wydajności konwersji światła w komórkach fotowoltaicznych lub/i (b) obniżenie kosztów paneli PV poprzez zastosowanie tańszych materiałów lub technologii. W referacie omówione są prace mające na celu: (a) zastąpienie zbyt drogiego ITO warstwami ZnO o przewodnictwie metalicznym, (b) uproszczenie konstrukcji komórek PV oraz (c) znalezienie alternatywnych materiałów.
Despite of a large reductions of costs energy produced by solar panels is still too expensive. There are two approaches to change this situation: by (a) increase of device output and/or (b) reduction of device costs by use of cheaper alternative materials. In this article we discuss the latter approach – (a) replacement of ITO by ZnO with metallic conductivity, (b) change of device architecture, and (c) use of alternative materials.
Źródło:
Prace Instytutu Elektrotechniki; 2014, 264; 5-13
0032-6216
Pojawia się w:
Prace Instytutu Elektrotechniki
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Synthesis Pressure on Properties of Eu-Doped ZnO Nanopowders Prepared by Microwave Hydrothermal Method
Autorzy:
Rosowska, J.
Kaszewski, J.
Witkowski, B.
Wachnicki, Ł.
Godlewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1185714.pdf
Data publikacji:
2016-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Hx
81.07.Wx
81.20.Ka
78.60.Hk
Opis:
In the current research, europium doped ZnO nanopowders prepared by a microwave hydrothermal method are investigated. The effects of synthesis pressure on the morphologies, crystal structures, and optical properties of Eu-doped ZnO were analyzed by scanning electron microscopy, X-ray diffraction, cathodo- and photoluminescence. From our investigations it can be concluded that the synthesis pressure strongly influences the surface morphology. With the increase of the synthesis pressure from 2 MPa to 10 MPa significant changes can be observed. An increase of the mean crystallites sizes and change of the intensity ratio between the near band edge and defect related deep level emission band of ZnO were observed.
Źródło:
Acta Physica Polonica A; 2016, 130, 5; 1205-1208
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
(Zn,Cu)O Films by Atomic Layer Deposition - Structural, Optical and Electric Properties
Autorzy:
Łukasiewicz, M.
Witkowski, B.
Wachnicki, Ł.
Kopalko, K.
Gierałtowska, S.
Wittlin, A.
Jaworski, M.
Guziewicz, E.
Godlewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1492571.pdf
Data publikacji:
2011-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.55.Ln
68.55.Nq
78.66.Hf
81.15.Kk
Opis:
ZnCuO thin films have been deposited on silicon, glass and quartz substrates by atomic layer deposition method, using reactive organic precursors of zinc and copper. As zinc and copper precursors we applied diethylzinc and copper(II) acetyloacetonate. Structural, electrical and optical properties of the obtained ZnCuO layers are discussed based on the results of scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, atomic force microscopy, the Hall effect and photoluminescence investigations.
Źródło:
Acta Physica Polonica A; 2011, 120, 6A; A-034-A-036
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fermi-Edge Singularity in Excitonic Spectra of Modulation Doped AlGaAs/GaAs Quantum Wells
Autorzy:
Bugajski, M.
Regiński, K.
Godlewski, M.
Wesołowski, M.
Holtz, P. O.
Buyanov, A. V.
Monemar, B.
Powiązania:
https://bibliotekanauki.pl/articles/1950741.pdf
Data publikacji:
1996-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.35.+z
85.30.De
Opis:
The dynamic response of an electron Fermi sea to the presence of optically generated holes gives rise to an enhanced interaction of correlated electron-hole pairs near the Fermi level, resulting in an enhanced oscillator strength for optical transitions, referred to as the Fermi-edge singularity. We studied this effect in modulation-doped quantum wells which provide confined dense Fermi sea, spatially separated from dopant atoms, easily accessible for investigations under low excitation conditions. The Fermi-edge singularity was observed in both photoluminescence and photoluminescence excitation experiments, although in the case of photoluminescence the samples had to be either co-doped with acceptors in the wells to provide necessary localization of holes or designed to allow for nearly resonant scattering between the electronic states near the Fermi energy and the next unoccupied subband of the 2D electron gas.
Źródło:
Acta Physica Polonica A; 1996, 90, 4; 751-754
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Growth Conditions on Exciton Properties in Thin Quantum Wells of GaAs/AlGaAs
Autorzy:
Godlewski, M.
Bergman, J. P.
Holtz, P. O.
Monemar, B.
Bugajski, M.
Regiński, K.
Kaniewska, M.
Powiązania:
https://bibliotekanauki.pl/articles/1933743.pdf
Data publikacji:
1995-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
73.20.Fz
71.35.+z
Opis:
Exciton properties in growth interrupted quantum wells of GaAs/AlGaAs are compared with those observed for structures grown without growth interruption during the molecular beam epitaxy process. We report observation of quasi-localized excitons in quantum well structures grown without growth interruptions. Quasi-localized excitons drift towards the states of a lower potential energy in the quantum well. For growth interrupted MBE structures islands with a constant quantum well thickness become large compared to the exciton radius. Free or lightly localized excitons are observed in that case.
Źródło:
Acta Physica Polonica A; 1995, 88, 4; 719-722
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inter-Island Energy Transfer in AlGaAs/GaAs Quantum Wells Grown by Molecular Beam Epitaxy
Autorzy:
Godlewski, M.
Holz, P. O.
Bergman, J. P.
Monemar, B.
Regiński, K.
Bugajski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1952469.pdf
Data publikacji:
1996-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.66.Fd
78.47.+p
73.20.Jc
Opis:
The results of photoluminescence, time-resolved photoluminescence, photoluminescence excitation and photoluminescence kinetics studies are presented for a Al$\text{}_{0.3}$Ga$\text{}_{0.7}$As/GaAs quantum well system grown without growth interruptions at the interfaces. The time-resolved photoluminescence measurements show drift of excitons towards lower energy states induced in a quantum well by potential fluctuations. We present also a first direct evidence for migration of free excitons from the 24 to 25 ML regions of the quantum well and interpret these results within a linear rate model, deriving the transition rate of 290 ps$\text{}^{-1}$. Such inter-island migration processes have been observed till now only in growth interrupted structures.
Źródło:
Acta Physica Polonica A; 1996, 90, 5; 1007-1011
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fermi-Edge Singularity in Luminescence Spectra of P-Type Modulation Doped AlGaAs/GaAs Quantum Wells
Autorzy:
Bugajski, M.
Godlewski, M.
Regiński, K.
Holtz, P. O.
Bergman, J. P.
Monemar, B.
Powiązania:
https://bibliotekanauki.pl/articles/1969046.pdf
Data publikacji:
1998-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.55.Px
73.20.Dx
Opis:
We have studied an enhancement of the oscillator strength for optical transitions near the Fermi energy in p-type modulation-doped quantum wells, which, so far, deserved much less attention than analogous n-type systems, because of the complicated valence band structure involved. The relatively wide (L=150 Å) quantum wells and high doping levels were used, containing more than one occupied subband. The enhancement in the photoluminescence intensity at the Fermi energy resulted from the strong correlation and multiple scattering of holes near the Fermi edge by the localized electrons.
Źródło:
Acta Physica Polonica A; 1998, 94, 2; 265-270
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exciton Dynamics in CdTe/CdMnTe Multiquantum Well Structures Grown by Molecular Beam. Epitaxy on GaAs Substrate
Autorzy:
Godlewski, M.
Koziarska, B.
Suchocki, A.
Karczewski, G.
Wojtowicz, T.
Kossut, J.
Bergman, J.
Monemar, B.
Powiązania:
https://bibliotekanauki.pl/articles/1934057.pdf
Data publikacji:
1995-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.60.-p
78.47.+p
73.20.Fz
71.35.+z
Opis:
The results of picosecond photoluminescence kinetics of four different CdTe/CdMnTe multiquantum well structures grown by MBE on GaAs substrates are presented. The experimental results show that excitons in CdTe quantum wells are strongly localized by potential fluctuations. Photoluminescence decay times of the localized excitons are considerably shorter (about 120 ps) than those reported for free or quasi-free excitons. An influence of Mn in the barriers on exciton properties is demonstrated. For narrow quantum wells as well as for the multiquantum well structure with the highest Mn mole fraction the excitons migrate during their decay to the states with a lower potential energy. Longer decay times are observed for quasi-localized excitons. We show also that for strongly localized excitons the energy transfer between localized and donor bound excitons is less efficient.
Źródło:
Acta Physica Polonica A; 1995, 88, 5; 985-989
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies