'Forbidden' reflections in resonant diffraction of synchrotron radiation in yttrium aluminum garnet Y{sub 3}Al{sub 5}O{sub 12}

Journal Article · Sat Jan 15 04:00:00 EST 2011 · Journal of Experimental and Theoretical Physics

DOI:https://doi.org/10.1134/S1063776110061147· OSTI ID:22028191

Mukhamedzhanov, E Kh; Kovalchuk, M V; Borisov, M M ^[1]; Oreshko, A P ^[2]; Dmitrienko, V E ^[3]

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1. 'Kurchatov Institute' Russian Research Center (Russian Federation)
2. Moscow State University (Russian Federation)
3. Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

The purely resonant Bragg reflections (13, 13, 0) and (14, 0, 0) in yttrium aluminum garnet Y{sub 3}Al{sub 5}O{sub 12} at energies near the K absorption edge of yttrium have been studied experimentally and theoretically. The anisotropic tensor atomic factor of yttrium corresponding to dipole-dipole resonance transitions depends on three independent parameters changing with energy. The intensities of the reflections (14, 0, 0) and (13, 13, 0) are shown to depend on the parameter difference f{sub 1}(E) - f{sub 2}(E) and the parameter f{sub 3}(E), respectively, which are attributable to distortions of the wave functions of the excited atoms and change greatly with photon energy E. Studying various reflections has allowed one to determine the various components of the tensor atomic factor and to compare them with the results of numerical calculations.

• OSTI ID: 22028191
• Journal Information: Journal of Experimental and Theoretical Physics, Journal Name: Journal of Experimental and Theoretical Physics Journal Issue: 1 Vol. 112; ISSN JTPHES; ISSN 1063-7761
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINATES
ANISOTROPY
BRAGG REFLECTION
COMPARATIVE EVALUATIONS
DIPOLES
GARNETS
K ABSORPTION
PHOTONS
SYNCHROTRON RADIATION
TENSORS
WAVE FUNCTIONS
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS