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Multiple Time Scales in Diffraction Measurements of Diffusive Surface Relaxation

Aaron Fleet·Darren Dale·A. R. Woll·Y. Suzuki·J. D. Brock
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Abstract

We grew SrTiO3 on SrTiO3 (001) by pulsed laser deposition, using x-ray scattering to monitor the growth in real time. The time-resolved small angle scattering exhibits a well-defined length scale associated with the spacing between unit cell high surface features. This length scale imposes a discrete spectrum of Fourier components and rate constants upon the diffusion equation solution, evident in multiple exponential relaxation of the "anti-Bragg" diffracted intensity. An Arrhenius analysis of measured rate constants confirms that they originate from a single activation energy.

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Aaron Fleet, Darren Dale, A. R. Woll, Y. Suzuki, J. D. Brock. 2005-04-11. Multiple Time Scales in Diffraction Measurements of Diffusive Surface Relaxation. https://doi.org/10.1103/physrevlett.96.055508

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