Results 221 to 230 of about 1,547,483 (263)

Separation of optical anisotropies by angular dependent reflection anisotropy spectroscopy

Applied Physics Letters, 2002
Double rubbing of polymer films, which finds applications in modern liquid crystal devices, has been investigated using reflection anisotropy spectroscopy (RAS) and atomic force microscopy. A method of gauging the relative strength of rubbing in two different directions, based upon the dependence of observed RAS signals on the sample azimuthal angle ...
B. F. Macdonald, R. J. Cole
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The optical anisotropy of Pt(100) studied by reflection anisotropy spectroscopy

Physica Status Solidi (a), 1995
The optical anisotropy of the Pt(100) hex-R0.7° reconstructed phase is studied with reflection anisotropy spectroscopy. The transition from the hex-R0.7° to the Pt(1 x 1) structure is also studied. The spectrum of Pt(100) hex-R0.7° is found to be dominated by surface polariton-like absorption due to the wavy nature of the first layer superstructure ...
A. Borg, O. Hunderi, W. Richter, J. Rumberg, H. J. Venvik   +4 more
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Reflection anisotropy spectroscopy of the oxidized diamond (001) surface

Journal of Physics: Condensed Matter, 2009
We report reflection anisotropy spectroscopy (RAS) measurements of the oxidized (001) surface of a type IIb natural diamond. These measurements were made possible due to recent developments in diamond surface preparation. We compare RAS results from the hydrogenated, clean and oxidized C(001) surface and demonstrate that RAS is sensitive to the ...
M, Schwitters, D S, Martin, P, Unsworth, T, Farrell, J E, Butler, P, Weightman   +5 more
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Sum rules in surface differential reflectivity and reflectance anisotropy spectroscopies

Applied Surface Science, 2001
Abstract The sum rule for the imaginary part of the dielectric function e″ can help in discriminating surface and bulk-related optical transitions, by means of the number of electrons taking part in the transitions. This is particularly simple in the region below the main critical points of the bulk band structure (below 3.5 eV for Si, below 2.2 eV ...
G Chiarotti, P Chiaradia, F Arciprete, C Goletti   +3 more
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Analysis of the phase signal in reflection anisotropy spectroscopy

Semiconductor Science and Technology, 1995
In this study the analysis of reflection anisotropy signals reveals that an unusual behaviour of the phase signal may occur in the presence of weakly anisotropic surfaces. It will be shown that the measured lineshape has to be considered with extreme care if a single-phase lock-in amplifier is used in the experimental set-up. It not only depends on the
W Dietrich, M von der Emde, D R T Zahn
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Molecular orientation studied by reflection anisotropy spectroscopy

physica status solidi (b), 2010
AbstractA description of the reflection anisotropy spectroscopy (RAS) results from oriented thin films is presented. The RAS signals of a 1 nm thick film are simulated to investigate the effect of molecular tilt on the RAS response of the system. Whilst the spectroscopic measurements themselves appear to be relatively insensitive to the effects of the ...
P. D. Lane, G. E. Isted, R. J. Cole
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Adsorbate Azimuthal Orientation from Reflectance Anisotropy Spectroscopy

Physical Review Letters, 1998
We have determined the azimuthal orientation of an adsorbate on a metal surface from an intramolecular-transition-derived feature in reflectance anisotropy spectroscopy (RAS).
B. G. Frederick, J. R. Power, R. J. Cole, C. C. Perry, Q. Chen, S. Haq, Th. Bertrams, N. V. Richardson, P. Weightman   +8 more
core   +4 more sources

Reflection Anisotropy Spectroscopy: A New Probe for the Solid-Liquid Interface

Physical Review Letters, 2000
Introducing reflection anisotropy spectroscopy (RAS) as a new probe for solid-liquid interfaces, we present results for the Au(110)/electrolyte interface which serves as a model system. We demonstrate that RAS is sensitive to surface phase transitions, step morphology, and electronic surface states.
, Sheridan, , Martin, , Power, , Barrett, , Smith, , Lucas, , Nichols, , Weightman   +7 more
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Transient Reflective-Polarization Spectroscopy of Hidden Anisotropy in Cubic Crystals

Ultrafast Phenomena, 1994
It is often anticipated that the linear optical properties of GaAs as a cubic material are isotropic. More careful consideration, however shows that spatial dispersion terms in the optical response lead to a small linear birefringence in this crystal. The crystal anisotropy becomes more pronounced in the nonlinear optical response where the symmetry of
N. I. Zheludev, A. R. Bungay, S. V. Popov, Yu. P. Svirko   +3 more
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Stress-induced optical anisotropy in polycrystalline copper studied by reflection anisotropy spectroscopy

Journal of Physics D: Applied Physics, 2003
The optical properties of polycrystalline copper subjected to tensile stress are monitored in situ and in real time using reflection anisotropy spectroscopy (RAS). It is shown that RAS allows investigation of the plastic regime. Here, in contrast to the Hooke's law regime, the stress-induced RAS lineshape is found to be dependent on the applied stress.
R J Cole, S Kheradmand, D D Higgins, F Madani, B F Macdonald, V Koutsos, J R Blackford   +6 more
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