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1

Elastic Properties of Zinc Blende MnTe

100%

Djemia P., Roussigné Y., Stashkevich A., Szuszkiewicz W., Gonzalez Szwacki N., Dynowska E., Janik E., Kowalski B., Karczewski G., Bogusławski P., Jouanne M., Morhange J.

Acta Physica Polonica A

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2004

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vol. 106

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issue 2

239-247

EN

The Brillouin light scattering was used to investigate elastic properties of the zinc blende, MBE-grown MnTe layer that was deposited on a (001) GaAs substrate covered by CdTe buffer layer. The three elastic constants of the zinc blende MnTe, namely c_{11}, c_{12}, and c_{44}, were directly determined for the first time from the frequency of the Rayleigh mode, of the pseudo-surface mode, and of the shear horizontal bulk mode traveling parallel to the layer surface. The value of c_{11} was checked using the frequency of longitudinal bulk waves propagating at different angles from the normal of the layer plane. This value was also independently determined by results of the folding of acoustic phonons, observed for MnTe/CdTe superlattices by the Raman scattering. Finally, the bulk modulus given by the formula B=(c_{11}+2c_{12})/3 was determined for zinc blende MnTe by ab initio calculations making use of the density functional theory and atomic pseudopotentials; spin polarization of MnTe was taken into account. A satisfactory agreement between theoretical and experimental values was obtained.

2

Light Scattering Investigations of Magnetic Anisotropies in Ultrathin Epitaxial Co Films

100%

Hillebrands B., Krams P., Fassbender J., Mathieu C., Güntherodt G., Jungblut R., Johnson M.

Acta Physica Polonica A

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1994

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vol. 85

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issue 1

179-193

EN

Using Brillouin light scattering, the properties of magnetic anisotropies in ultrathin epitaxial Co films grown on single-crystal Cu substrates are investigated. All relevant magnetic anisotropy contributions are determined, in situ in an ultrahigh vacuum system for the (001)-oriented films, as well as ex situ for other film orientations, which are covered with a Cu cap layer. For (001)-oriented films we find a large in-plane anisotropy contribution of fourfold symmetry. For this contribution the volume and the surface part cancel to zero at the same thickness as found for the onset of ferromagnetic order. This finding is indicative for a stabilization of ferromagnetic order in Co/Cu(001) by in-plane anisotropy contributions. In (1 1 13)-oriented films, which are composed of (001)-terraces aligned along the [11̅0]-direction and spaced by 6.5 atomic distances, an additional uniaxial in-plane anisotropy contribution is found which is identified as being of magneto-elastic origin. For (110)-oriented films three ranges of thickness dependence of the in-plane and out-of-plane anisotropy contributions are found which correlate in the thin-film regime with the growth properties. (111)-oriented films show a linear dependence of the perpendicular anisotropy on the reciprocal film thickness over the full investigated thickness range of 2 to 20 Å.

3

Angle Resolved Scattering Combined with Optical Profilometry as Tools in Thin Films and Surface Survey

100%

Marszałek K., Wolska N., Jaglarz J.

Acta Physica Polonica A

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2015

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vol. 128

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issue 1

81-86

EN

The work presents an application of two scanning optical techniques, i.e. optical profilometry and angle resolved scattering method. The first method measures the light reflected from a film during scan of the surface, while the second method measures light intensity as a function of the scattering angle. The angle resolved scattering and optical profilometry measurements, being complementary to the atomic force microscopy, give information about surface topography. Scattered radiation measured by angle resolved scattering and optical profilometry is a function of height and slope of microfacets. The analysis of images allows to determine the most important statistic surface parameters, like roughness, height distribution and autocorrelation length, in large wavelength range by the determination of power spectral density function. The fast Fourier transform of angle resolved scattering and optical profilometry images permits to determine the distribution of surface features in the inverse space, such as periodicity and anisotropy. In this paper the results obtained for porous SiO₂, SiO₂-TiO₂ blends, TiN and polymer thin films have been presented. The paper demonstrates the usefulness of the angle resolved scattering and optical profilometry for the surface and volume thin film inspection.

4

Elastooptic Constants of SrLaAlO_{4} and SrLaGaO_{4} Single Crystals Determined by Brillouin Scattering

100%

Drozdowski M., Pajączkowska A., Kasprowicz D., Ziobrowski P., Gloubokov A.

Acta Physica Polonica A

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1997

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vol. 92

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issue 1

177-181

EN

In this paper we report the elastooptic constants p_{ij} of strontium lanthanum aluminate, SrLaAlO_{4} and strontium lanthanum gallate SrLaGaO_{4} single crystals, which were determined at room temperature using Brillouin scattering method. In order to investigate the elastooptic constants of SrLaAlO_{4} and SrLaGaO_{4} single crystals, a substitution method proposed by Cummins and Schoen, and developed by Nelson and Lax was used. The obtained results are also discussed in terms of the nature defects which might arise in these crystals during growth process.

5

Anomalous Phase Transitions in LiCsSO_4 in the Compressible hcp Ising Model

100%

Lehmann-Szweykowska A., Kurzyński M., Wojciechowski R., Wiesner M., Mróz B.

Acta Physica Polonica A

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2012

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vol. 121

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issue 5-6

1108-1110

EN

Structural low-temperature phase transformations in LiCsSO_4 are analysed in a newly tailored simple model of the static soliton in the periodically modulated phases of the one-dimensional compressible Ising model. It is shown that the original hcp symmetry is crucial for understanding of the anomalous temperature-dependence of the Brillouin shift.

6

Measuring the Energy Landscape in Single Semiconductor Nanowires

63%

Smith L., Jackson H., Yarrison-Rice J., Jagadish C.

Acta Physica Polonica A

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2012

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vol. 122

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issue 2

316-320

EN

With the ability to design and control the physical structure of nanostructures to tune their electronic properties, it is increasingly important to measure the electronic structure of single nanostructures. Here we describe a number of experimental techniques for measuring the electronic structure of single semiconductor nanowires. The advantages, disadvantages and limitations of these methods will be described.

7

Sezawa and love modes in Co/Cu superlattices

63%

Błachowicz T.

Open Physics

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2003

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vol. 1

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issue 4

574-595

EN

In this paper detailed theoretical study and experimental results concerning acoustic surface and undersurface propagation modes in multilayered Co/Cu superlattices are provided. The theoretical approach was adopted from that of Adler and Farnel. Experimental results were obtained in Brillouin light-scattering measurements. The Sezawa and Love acoustic modes were observed as a result of boundary conditions at the interface between hexagonal and cubic structures.

Refine search results

Elastic Properties of Zinc Blende MnTe

Light Scattering Investigations of Magnetic Anisotropies in Ultrathin Epitaxial Co Films

Angle Resolved Scattering Combined with Optical Profilometry as Tools in Thin Films and Surface Survey

Elastooptic Constants of SrLaAlO_{4} and SrLaGaO_{4} Single Crystals Determined by Brillouin Scattering

Anomalous Phase Transitions in LiCsSO_4 in the Compressible hcp Ising Model

Measuring the Energy Landscape in Single Semiconductor Nanowires

Sezawa and love modes in Co/Cu superlattices