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arXiv · 1410.7572

Gradient bounds for a thin film epitaxy equation

Dong Li·Zhonghua Qiao·Tao Tang
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Abstract

We consider a gradient flow modeling the epitaxial growth of thin films with slope selection. The surface height profile satisfies a nonlinear diffusion equation with biharmonic dissipation. We establish optimal local and global wellposedness for initial data with critical regularity. To understand the mechanism of slope selection and the dependence on the dissipation coefficient, we exhibit several lower and upper bounds for the gradient of the solution in physical dimensions $d\le 3$.

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Dong Li, Zhonghua Qiao, Tao Tang. 2014-10-28. Gradient bounds for a thin film epitaxy equation. https://arxiv.org/abs/1410.7572

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