Wyniki wyszukiwania - Biblioteka Nauki

1

Element Specific Magnetometry Combining X-ray Circular with Linear Dichroism: Fundamentals and Applications

100%

Kowalik I.

Acta Physica Polonica A

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2015

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tom 127

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nr 3

831-849

EN

This article gives an overview of the use of X-ray absorption spectroscopy to characterize the magnetic properties for technologically important, low dimensional magnetic materials. An overview is given both for the experimental hardware, the measurements and the analysis of the spectra. The information obtained is discussed for metallic and semiconducting systems, using both the X-ray magnetic circular dichroism and the X-ray linear magnetic dichroism spectroscopy.

2

Element Specific Magnetometry Combining X-ray Circular with Linear Dichroism: Fundamentals and Applications (Acta Physica Polonica A 127, 831 (2015), ERRATUM)

100%

Kowalik I.

Acta Physica Polonica A

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2017

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tom 132

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nr 2

408

EN

This article gives an overview of the use of X-ray absorption spectroscopy to characterize the magnetic properties for technologically important, low dimensional magnetic materials. An overview is given both for the experimental hardware, the measurements and the analysis of the spectra. The information obtained is discussed for metallic and semiconducting systems, using both the X-ray magnetic circular dichroism and the X-ray linear magnetic dichroism spectroscopy.

3

Fano Resonance of Eu^{2+} and Eu^{3+} in (Eu,Gd)Te MBE Layers

32%

Orlowski B. , Kowalski B. , Dziawa P. , Pietrzyk M. , Mickievicius S. , Osinniy V. , Taliashvili B. , Kowalik I. , Story T. , Johnson R.

Acta Physica Polonica A

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2005

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tom 108

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nr 5

803-807

EN

Resonant photoemission spectroscopy, with application of synchrotron radiation, was used to study the valence band electronic structure of clean surface of (EuGd)Te layers. Fano-type resonant photoemission spectra corresponding to the Eu 4d-4f transition were measured to determine the contribution of 4f electrons of Eu^{2+} and Eu^{3+} ions to the valence band. The resonant and antiresonant photon energies of Eu^{2+} ions were found as equal to 141 V and 132 eV, respectively and for Eu^{3+} ions were found as equal to 146 eV and 132 eV, respectively. Contribution of Eu^{2+}4f electrons was found at the valence band edge while for Eu^{3+} it was located in the region between 3.5 eV and 8.5 eV below the valence band edge.

4

Photoemission Study of Mn 3d Electrons in the Valence Band of Mn/GeMnTe

32%

Pietrzyk M. , Kowalski B. , Orłowski B. , Knoff W. , Osinniy V. , Kowalik I. , Story T. , Johnson R.

Acta Physica Polonica A

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2007

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tom 112

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nr 2

275-281

EN

We present the results of the electronic band structure study of Ge_{0.9}Mn_{0.1}Te epilayers, clean and modified in situ by deposition of manganese atoms. The sets of resonant photoemission spectra were measured for the photon energy range covering the energy of Mn 3p→3d transition (45

5

MnAs Overlayer on GaN(000_1)-(1 x 1) - Its Growth, Morphology and Electronic Structure

32%

Kowalski B. , Kowalik I. , Iwanowski R. , Łusakowska E. , Sawicki M. , Sadowski J. , Grzegory I. , Porowski S.

Acta Physica Polonica A

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2004

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tom 105

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nr 6

645-650

EN

MnAs layer has been grown by means of MBE on the GaN(000_1)-(1 x 1) surface. Spontaneous formation of MnAs grains with a diameter of 30-60 nm (as observed by atomic force microscopy) occurred for the layer thickness bigger than 7 ML. Ferromagnetic properties of the layer with Curie temperature higher than 330 K were detected by SQUID measurements. Electronic structure of the system was investigated in situ by resonant photoemission spectroscopy for MnAs layer thickness of 1, 2, and 8 ML. Density of the valence band states of MnAs and its changes due to the increase in the layer thickness were revealed.

6

ZnCoO Films by Atomic Layer Deposition - Influence of a Growth Temperature οn Uniformity of Cobalt Distribution

26%

Łukasiewicz M. , Witkowski B. , Godlewski M. , Guziewicz E. , Sawicki M. , Paszkowicz W. , Łusakowska E. , Jakieła R. , Krajewski T. , Kowalik I. , Kowalski B.

Acta Physica Polonica A

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2009

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tom 116

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nr 5

921-923

EN

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.

7

Extra-Low Temperature Growth of ZnO by Atomic Layer Deposition with Diethylzinc Precursor

26%

Kowalik I. , Guziewicz E. , Kopalko K. , Yatsunenko S. , Godlewski M. , Wójcik A. , Osinniy V. , Krajewski T. , Story T. , Łusakowska E. , Paszkowicz W.

Acta Physica Polonica A

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2007

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tom 112

|

nr 2

401-406

EN

ZnO thin films were grown on silicon substrate by atomic layer deposition method. We explored double-exchange chemical reaction and used very volatile and reactive diethylzinc as a zinc precursor. These enables us to obtain zinc oxide thin films of high quality at extremely low growth temperature (90-200ºC). The films are polycrystalline as was determined by X-ray diffraction and show flat surfaces with roughness of 1-4 nm as derived from atomic force microscopy measurements. Photoluminescence studies show that an edge emission of excitonic origin is observed even at room temperature for all investigated ZnO layers deposited with the diethylzinc precursor.