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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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vol. 127

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issue 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

|

2017

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vol. 132

|

issue 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

33%

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

Acta Physica Polonica A

|

2005

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vol. 108

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issue 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

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

33%

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

Acta Physica Polonica A

|

2004

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vol. 105

|

issue 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.

5

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

33%

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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vol. 112

|

issue 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

6

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

27%

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

|

2009

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vol. 116

|

issue 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

27%

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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vol. 112

|

issue 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.

8

Magnetooptical Properties of (Ga,Fe)N Layers

27%

Papierska J., Rousset J., Pacuski W., Kossacki P., Golnik A., Nawrocki M., Gaj J., Suffczyński J., Kowalik I., Stefanowicz W., Sawicki M., Dietl T., Navarro-Quezada A., Faina B., Li T., Bonanni A.

Acta Physica Polonica A

|

2011

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vol. 120

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issue 5

921-923

EN

Magnetooptical properties of (Ga,Fe)N layers containing various concentrations of Fe-rich nanocrystals embedded in paramagnetic (Ga,Fe)N layers are reported. Previous studies of such samples demonstrated that magnetization consists of a paramagnetic contribution due to substitutional diluted Fe ions as well as of ferromagnetic and antiferromagnetic components originating from Fe-rich nanocrystals, whose relative abundance can be controlled by the growth conditions. The nanocrystals are found to broaden and to reduce the magnitude of the excitonic features. However, the ferromagnetic contribution, clearly seen in SQUID magnetometry, is not revealed by magnetic circular dichroism. Possible reasons for differences in magnetic response determined by magnetic circular dichroism and SQUID measurements are discussed.

Refine search results

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

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

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

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

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

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

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

Magnetooptical Properties of (Ga,Fe)N Layers