Results 251 to 260 of about 317,264 (286)

CALCULATION OF REFLECTANCE ANISOTROPY FOR SEMICONDUCTOR SURFACE EXPLORATION

EPIOPTICS-8, 2005
AbstractReflectance anisotropy spectroscopy (RAS) is exquisitely sensitive to probe surfaces, with many potential applications in determining surface geometries or monitoring material growth. Thanks to recent computational and methodological progress it has now become possible to calculate surface optical spectra accurately and with true predictive ...
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REFLECTANCE ANISOTROPY OF THE GaAs(001) SURFACE

Surface Review and Letters, 1994
By a combination of theoretical calculations and experiments, we have investigated the GaAs(001) surface and found the reflectance anisotropy (RA) to be extremely sensitive to the atomic configuration upon the surface. By performing a series of ab initio pseudopotential calculations of the optical response of the (2×4) surface reconstruction we find ...
S.J. MORRIS, J.M. BASS, D.I. WESTWOOD, D.A. WOOLF, C.C. MATTHAI, R.H. WILLIAMS, F. REINHARDT, J. RUMBERG, K.C. ROSE, W. RICHTER   +9 more
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Anisotropy in reflected GPS measurements of ocean winds

IGARSS 2003. 2003 IEEE International Geoscience and Remote Sensing Symposium. Proceedings (IEEE Cat. No.03CH37477), 2004
The probability density function (PDF) of the ocean surface slope can be estimated from the code-correlation waveform of reflected GPS signals. Anisotropy in this PDF is found to correspond to the local near surface wind direction, suggesting the ability to resolve this direction using scattered signals from two or more GPS satellites.
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Anisotropy of Granites: A Reflection of Microscopic Fabric

Géotechnique, 1969
Synopsis The Paper contains the results of an inquiry into the mechanical anisotropy of granites from three North American localities. An assumption of an ellipsoidal distribution of elastic moduli was found to be justified: the data suggest that the orthotropic elastic idealization may be suitable provided that non-linearity is accounted for ...
P. M. Douglass, B. Voight
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Ellipsoid estimation in coal reflectance anisotropy

Mathematical Geology, 1997
The procedure of fitting an ellipsoid to vitrinite reflectance anisotropy is described. Several authors on this subject use incorrect fitting formulae. The correct formulae are given and a least- squares procedure is developed to give confidence regions for the principal reflectances and their orientations.
Douglas Kelker, Willem Langenberg
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Real-time reflectance anisotropy spectroscopy of GaAs homoepitaxy

Applied Optics, 2020
Reflectance anisotropy spectroscopy (RAS) is a highly sensitive optical probe for the real-time study of the epitaxial growth of zincblende semiconductors. Here we report on (1) non-equilibrium RAS spectra acquired in real time during the homoepitaxial growth of GaAs, and (2) RAS spectra for GaAs surfaces under equilibrium with several arsenic ...
A, Lastras-Martínez, L E, Guevara-Macías, J G, Santiago-García, J, Ortega-Gallegos, I A, Ruiz-Alvarado, R, Martínez-Espinosa, D, Ariza-Flores, R, Castro-García, R E, López-Estopier, R E, Balderas-Navarro, L F, Lastras-Martínez   +10 more
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Infrared reflectance anisotropy of wurzite GaN

Journal of Applied Physics, 2009
We have measured the infrared reflectance anisotropy of bulk wurzite (0001) GaN. Reflectance difference (RD) spectra have been determined from the experimental reflectance for light polarization along the sample axes [01¯10] and [112¯0]. The spectra show an optical anisotropy around the frequency of the E1(LO) and A1(LO) GaN phonons.
M. C. Rodríguez-Aranda, A. G. Rodríguez, H. Navarro-Contreras, M. A. Vidal   +3 more
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Reflectivity and reflectance anisotropy of Si(100): a polarisable bond model

Surface Science, 1997
Abstract The reflectivity and reflectance anisotropy (RA) of the unreconstructed Si(100) surface are calculated using a model in which the semiconductor is a slab of polarisable bonds interacting by induced dipolar fields. Parameters for the calculations are obtained from ab initio calculations.
D. Herrendörfer, C.H. Patterson
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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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The Role Of Specular Reflectance In Surface Anisotropy

[Proceedings] IGARSS '92 International Geoscience and Remote Sensing Symposium, 2005
For smooth surfaces, specular reflection constitutes a major source of anisotropy in the surface bidirectional reflectance and introduces a strong illumination angle dependence in diurnal albedo. A prior formulation has been employed by the authors to account for the surface anisotropy of other natural surfaces.
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