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1

Effect of Temperature on the Ion Beam Induced Luminescence of Oxide Powders Doped with Rare Earth Elements

100%

Gawlik G., Panczer G., Moncoffre N., Jagielski J.

Acta Physica Polonica A

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2013

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vol. 123

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issue 5

920-922

EN

The hydrogen ion beam induced luminescence of gadolinium oxide Gd_2O_3 doped with 1% of holmium (Ho) and 1% of bismuth (Bi) was investigated. Degradation of the holmium related 549 nm ion beam induced luminescence line intensity during hydrogen ion irradiation was observed. Two different mechanisms of the ion beam induced luminescence degradation has been proposed: the first one related to the accumulation of ion induced target material damage and the second mechanism related to the target temperature growth during ion beam bombardment. The experimental method for separation of both mechanisms effects was proposed and demonstrated.

2

Cathodoluminescence Studies of Polytype Structure in Zn_{1-x}Mg_{x}Se

100%

Cichos A., Firszt F., Falke U., Lenzner J., Męczyńska H., Hietschold M.

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vol. 95

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issue 2

269-274

EN

Zn_{1-x}Mg_{x}Se crystals grown by Bridgman method show spatial transition from sphalerite (3C) to wurzite structure (2H) with increasing Mg content (x). Within the transition range, near x=0.19, coexistence of hexagonal and cubic structure results in the formation of polytype sequences of 3C-8H-4H-2H. We have investigated the spatial distribution of the polytypes in Zn_{1-x}Mg_{x}Se mixed crystals with a value of x close to that of the phase transition using spectrally as well as spatially resolved cathodoluminescence. Three emission bands in the cathodoluminescence spectrum have been observed, two strong lines at 2.99 eV and 2.965 eV, and a weak shoulder at 2.95 eV. The lines at 2.965 and 2.99 eV are known in the literature as an exciton recombination in the 8H and 4H polytype structure. We have found the third one at 2.95 eV to be due to luminescence in the 3C structure. These results demonstrate the usefulness of cathodoluminescence measurements for investigations of spatial distribution of inhomogeneities of mixed semiconductors.

3

Cathodoluminescence Study of Cd_{1-x}Mn_{x}Te and Zn_{1-x}Mn_{x}Te

63%

Hołda A., Rodzik A., Melnikov A. A., Żukowski P. W.

Acta Physica Polonica A

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1995

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vol. 88

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issue 4

739-742

EN

The cathodoluminescence spectra for Cd_{1-x}Μn_{x}Te (0 < x ≤ 0.7) and Zn_{1-x}Mn_{x}Te (0 < x ≤ 0.6) at room and liquid nitrogen temperature have been presented and discussed. Especially, the influence of increasing temperature and Mn content on cathodoluminescence spectra. The cathodoluminescence emission in Ζn_{1-x}Mn_{x}Te (Cd_{1-x}Μn_{x}Te) centered at ≈ 1.95 eV (2.0 eV) and ≈ 2.2 eV (2.5 eV) are ascribed to Stokes-shifted ^{4}Τ_{1}(^{4}G) → ^{6}A_{1}(^{6}S) and ^{4}Τ_{2}(^{4}G) → ^{6}A_{1}(^{6}S) internal transitions of Mn^{+2} within the 3d^{5} state, respectively.

4

Swift Xe^{26+} Ion Irradiation Effect on Luminescent Properties of Undoped and Cd-Doped ZnO Films

63%

Myroniuk D., Lashkarev G., Shtepliuk I., Skuratov V., Reszka A., Kowalski B.

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vol. 126

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issue 5

1199-1202

EN

Here we report the effect of the irradiation by 167 MeV Xe^{26+} ions (in the fluence range up to 3× 10^{12} ions/cm^2) on the undoped and Cd-doped (0.4, 0.5 at.%) ZnO films deposited by radiofrequency magnetron sputtering. As-grown and irradiated samples were investigated by cathodoluminescence spectroscopy. It was found that the radiation causes a decrease in intensity of luminescent peaks and a redistribution of the radiative recombination channels. We revealed that the cadmium incorporation into ZnO lattice enhances the radiation resistance of ZnO film.

5

Structure and Cathodoluminescence of Y₂O₃:Eu Thin Films obtained at Different Conditions

51%

Bordun I., Bordun O., Kukharskyy I., Tsapovska Z.

Acta Physica Polonica A

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2018

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vol. 133

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issue 4

914-917

EN

The structure of the surface and spectra of the cathodoluminescence of Y₂O₃:Eu thin films when changing the activator concentration in the range 1.0-7.5% by mole obtained by RF sputtering were investigated. On the base of the shape of the cathodoluminescence spectra at different concentrations of the activator, the possibility of irregular solutions creating of yttrium and europium oxides and the structural features of the small and large crystallites forming the film Y₂O₃:Eu is shown. The dependence of the cathodoluminescence intensity on the energy of the exited electrons and current density of electron irradiation was established.

6

Cathodoluminescence Profiling of InGaN-Based Quantum Well Structures and Laser Diodes - In-Plane Instabilities of Light Emission

51%

Godlewski M., Ivanov V., Goldys E., Phillips M., Böttcher T., Figge S., Hommel D., Czernecki R., Prystawko P., Leszczynski M., Perlin P., Grzegory I., Porowski S.

Acta Physica Polonica A

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2003

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vol. 103

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issue 6

689-694

EN

Instabilities of light emission and also of stimulated emission in series of GaN epilayers and InGaN quantum well structures, including laser diode structures, are studied. A stimulated emission is observed under electron beam pumping. This enabled us to study light emission properties from laser structures and their relation to microstructure details. We demonstrate large in-plane fluctuations of light emission and that these fluctuations are also present for excitation densities larger than the threshold densities for the stimulated emission.

7

The Effect of Synthesis Pressure on Properties of Eu-Doped ZnO Nanopowders Prepared by Microwave Hydrothermal Method

51%

Rosowska J., Kaszewski J., Witkowski B., Wachnicki Ł., Godlewski M.

Acta Physica Polonica A

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2016

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vol. 130

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issue 5

1205-1208

EN

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.

8

Effect of Secondary Electroluminescence on Cathodoluminescence and Other Luminescence Measurements

51%

Pluska M., Czerwinski A., Szerling A., Ratajczak J., Kątcki J.

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vol. 125

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issue 4

1027-1032

EN

Cathodoluminescence and photoluminescence measurements are commonly accepted as revealing local properties of a specimen region excited by a beam of electrons or photons. However, in the presence of a strong electric field (e.g. a junction) an electron (or light/laser) beam-induced current is generated, which spreads over the structure. A secondary non-local electroluminescence, generated by this current and detected together with the expected luminescence signal, may strongly distort measurement results. This was confirmed by cathodoluminescence measurements on test structures prepared by focused ion beam on AlGaAs/GaAs/InGaAs laser heterostructures. Methods for minimizing the distortion of measured luminescence signals are presented.

9

Dependence of Nanoelectronic-Structure Defect Detection by Cathodoluminescence on Electron Beam Current

51%

Pluska M., Czerwinski A., Ratajczak J., Szerling A., Kątcki J.

Acta Physica Polonica A

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2009

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vol. 116

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issue S

S-86-S-88

EN

The dependence of defect detection by cathodoluminescence in a scanning electron microscope on the electron beam current is considered. The examined specimens are AlGaAs/GaAs laser heterostructures with InGaAs quantum well. It is shown that for low electron beam currents, which are typically used, the uniform cathodoluminescence is observed, while for the increasing high electron beam current the oval defects become more and more visible. The influence of electrical properties of the structure on the luminescence detection is explained.

10

Allocation and Properties of Iron States in Cd_{1-x}Fe_{x}Te in Forbidden Gap Energy Range

51%

Hołda A., Rodzik A., Melnikov A., Żukowski P.

Acta Physica Polonica A

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1995

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vol. 87

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issue 2

357-360

EN

The use of different experimental methods (reflectivity, absorption, photoconductivity and cathodoluminescence) allowed us to confirm the existence of the deep donor-like state of iron and present allocation and properties of the iron states in Cd_{1-y}Fe_{x}Te (0 ≤ x ≤ 0.05) at 300 K and 77 K in the forbidden gap energy range. It was concluded that the increase in width of the forbidden gap with the change of temperature from 300 K to 77 K leads mainly to the rise of the energy distance between the donor-like iron state ^{5}E and the bottom of the conduction band.

11

Cathodoluminescence Profiling for Checking Uniformity of ZnO and ZnCoO Thin Films

51%

Witkowski B., Łukasiewicz M., Wolska E., Kopalko K., Kowalski B., Guziewicz E., Godlewski M.

Acta Physica Polonica A

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2011

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vol. 119

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issue 5

675-677

EN

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.

12

Microscopic Luminescence Properties of ZnO and ZnO Based Heterostructures

51%

Bertram F., Christen J.

Acta Physica Polonica A

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2006

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vol. 110

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issue 2

103-110

EN

The optical properties of excitonic recombinations in ZnO are investigated by spatially and spectrally resolved cathodoluminescence measurements. The relevance of cathodoluminescence microscopy as a spatially resolved luminescence technique as a simple but very powerful characterization method is stressed out in discussions of a wide variety of appropriate examples. A thorough discussion of the various features of the cathodoluminescence of an undoped ZnO bulk crystal, epitaxially grown ZnO and MgZnO/ZnO/MgZnO quantum well structure is given. Particular attention is devoted to the impact of the internal electrical fields, e.g. the Franz-Keldysh effect in ZnO. Furthermore, this study focuses on the spectral variations as a function of depth to the interface in ZnO homo- and heterostructures. Our aim is to establish the nature of the optical transitions influenced by internal fields, defects and impurity doping in ZnO/GaN and ZnO/ZnO interfaces. This review covers also the vertical transport, diffusion and capture of carriers in a MgZnO/ZnO/MgZnO quantum well structure.

13

Do We Understand Magnetic Properties of ZnMnO?

51%

Godlewski M., Wójcik A., Kopalko K., Ivanov V., Wilamowski Z., Jakieła R., Guziewicz E., Szczepanik A., Dłużewski P., Chikoidze E., Barjon J., Dumont Y., Putkonen M., Niinistö L., Tang D.

Acta Physica Polonica A

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2007

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vol. 112

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issue 2

261-267

EN

Optical and magnetic properties of ZnMnO films are discussed based on the results of cathodoluminescence, photoluminescence, and magneto-photoluminescence investigations. We show that photoluminescence/cathodoluminescence emissions are strongly quenched and become in-plane inhomogeneous in samples with increased Mn fractions. Strong polarization of photoluminescence is observed, even though excitonic lines do not shift and are not split at magnetic fields up to 6 T.

14

Relationship between Sample Morphology and Carrier Diffusion Length in GaN Thin Films

51%

Godlewski M., Goldys E., Phillips M., Böttcher T., Figge S., Hommel D., Czernecki R., Prystawko P., Leszczynski M., Perlin P., Wisniewski P., Suski T., Bockowski M., Grzegory I., Porowski S.

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issue 4-5

627-632

EN

Scanning and spot-mode cathodoluminescence investigations of homo- and hetero-epitaxial GaN films indicate a surprisingly small influence of their microstructure on overall intensity of a light emission. This we explain by a correlation between structural quality of these films and diffusion length of free carriers and excitons. Diffusion length increases with improving structural quality of the samples, which, in turn, enhances the rate of nonradiative recombination on structural defects, such as dislocations.

15

Cathodoluminescence Measurements at Liquid Helium Temperature of Poly- and Monocrystalline ZnO Films

51%

Witkowski B., Wachnicki Ł., Jakieła R., Guziewicz E., Godlewski M.

Acta Physica Polonica A

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2011

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vol. 120

|

issue 6A

A-28-A-30

EN

Scanning electron microscopy, cathodoluminescence and secondary ion mass spectroscopy investigations are used to study an inter-link between structural quality, elements distribution and light emission properties of ZnO poly- and monocrystalline films grown by the atomic layer deposition. Cathodoluminescence and scanning electron microscopy investigations were performed at liquid helium temperature for four different types of ZnO films deposited on different substrates.

16

Light Emission Properties of GaN-Based Laser Diode Structures

51%

Godlewski M., Phillips M., Czernecki R., Targowski G., Perlin P., Leszczyński M., Figge S., Hommel D.

Acta Physica Polonica A

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2005

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vol. 108

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issue 4

675-680

EN

Cathodoluminescence is applied for evaluation of in-depth and in-plane variations of light emission from two types of GaN-based laser diode structures. We evaluate in-depth properties of the laser diode emission and demonstrate that potential fluctuations still affect emission of laser diodes for e-beam currents above thresholds for a stimulated emission.

17

Ion and Electron Beam Induced Luminescence οf Rare Earth Doped YAG Crystals

23%

Gawlik G., Sarnecki J., Jóźwik I., Jagielski J., Pawłowska M.

Acta Physica Polonica A

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2011

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vol. 120

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issue 1

181-183

EN

The aim of this work was the evaluation of ion-beam induced luminescence for the characterization of luminescent oxide materials containing rare earth elements. The yttrium aluminium garnet epilayers doped with Nd, Pr, Ho, and Tm atoms were used. The ion-beam induced luminescence spectra were excited using 100 keV H_2^{+} ion beam and were recorded in the wavelengths ranging from 300 nm up to 1000 nm. The separate parts of the surface of the same samples were used for ion-beam induced luminescence and cathodoluminescence experiments. Cathodoluminescence spectra have been recorded in the range from 370 nm up to 850 nm at 20 keV e-beam in scanning electron microscope equipped with a grating spectrometer coupled with a photomultiplier. The observed narrow ion-beam induced luminescence lines can be ascribed to the well known radiative transitions in the rare-earth ions in the YAG crystals. The cathodoluminescence spectra reveal essentially the same emission lines as ion-beam induced luminescence. The decrease of the ion-beam induced luminescence lines intensity has been observed under the increasing ion fluences. The ion-beam induced luminescence may be used for characterization of transparent luminescent materials as an alternative method for cathodoluminescence and can be especially useful for observation of ion-beam damage formation in crystals.

Refine search results

Effect of Temperature on the Ion Beam Induced Luminescence of Oxide Powders Doped with Rare Earth Elements

Cathodoluminescence Studies of Polytype Structure in Zn_{1-x}Mg_{x}Se

Cathodoluminescence Study of Cd_{1-x}Mn_{x}Te and Zn_{1-x}Mn_{x}Te

Swift Xe^{26+} Ion Irradiation Effect on Luminescent Properties of Undoped and Cd-Doped ZnO Films

Structure and Cathodoluminescence of Y₂O₃:Eu Thin Films obtained at Different Conditions

Cathodoluminescence Profiling of InGaN-Based Quantum Well Structures and Laser Diodes - In-Plane Instabilities of Light Emission

The Effect of Synthesis Pressure on Properties of Eu-Doped ZnO Nanopowders Prepared by Microwave Hydrothermal Method

Effect of Secondary Electroluminescence on Cathodoluminescence and Other Luminescence Measurements

Dependence of Nanoelectronic-Structure Defect Detection by Cathodoluminescence on Electron Beam Current

Allocation and Properties of Iron States in Cd_{1-x}Fe_{x}Te in Forbidden Gap Energy Range

Cathodoluminescence Profiling for Checking Uniformity of ZnO and ZnCoO Thin Films

Microscopic Luminescence Properties of ZnO and ZnO Based Heterostructures

Do We Understand Magnetic Properties of ZnMnO?

Relationship between Sample Morphology and Carrier Diffusion Length in GaN Thin Films

Cathodoluminescence Measurements at Liquid Helium Temperature of Poly- and Monocrystalline ZnO Films

Light Emission Properties of GaN-Based Laser Diode Structures

Ion and Electron Beam Induced Luminescence οf Rare Earth Doped YAG Crystals