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Controlling surface morphologies by time-delayed feedback

M. Block·B. Schmittmann·E. Schoell
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Abstract

We propose a new method to control the roughness of a growing surface, via a time-delayed feedback scheme. As an illustration, we apply this method to the Kardar-Parisi-Zhang equation in 1+1 dimensions and show that the effective growth exponent of the surface width can be stabilized at any desired value in the interval [0.25,0.33], for a significant length of time. The method is quite general and can be applied to a wide range of growth phenomena. A possible experimental realization is suggested.

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M. Block, B. Schmittmann, E. Schoell. 2007-01-09. Controlling surface morphologies by time-delayed feedback. https://doi.org/10.1103/physrevb.75.233414

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