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Dynamical Diffraction Theory for Wave Packet Propagation in Deformed Crystals

Kei Sawada·Shuichi Murakami·Naoto Nagaosa
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Abstract

We develop a theory for the trajectory of an x ray in the presence of a crystal deformation. A set of equations of motion for an x-ray wave packet including the dynamical diffraction is derived, taking into account the Berry phase as a correction to geometrical optics. The trajectory of the wave packet has a shift of the center position due to a crystal deformation. Remarkably, in the vicinity of the Bragg condition, the shift is enhanced by a factor $ω/Δω$ ($ω$: frequency of an x ray, $Δω$: gap frequency induced by the Bragg reflection). Comparison with the conventional dynamical diffraction theory is also made.

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Kei Sawada, Shuichi Murakami, Naoto Nagaosa. 2006-04-22. Dynamical Diffraction Theory for Wave Packet Propagation in Deformed Crystals. https://doi.org/10.1103/physrevlett.96.154802

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