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arXiv · 1703.10257

Negative bulk modulus and possibility of loss of elastic stability near tricritical transitions in thin films on substrates

A. P. Levanyuk·S. A. Minyukov·I. B. Misirlioglu
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Abstract

Within the Landau-like approach we study anomalies of elastic moduli at phase transitions in thin films on substrates. We consider the case where, similar to many experimental cases, the first-order transition in free crystal would convert into a second order in the film if the system remained homogeneous. It is shown, however, that apart from its questionable thermodynamic profitability, the homogeneous state of low-symmetry phase may become absolutely unstable which is signaled by changing of sign of its bulk modulus.

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A. P. Levanyuk, S. A. Minyukov, I. B. Misirlioglu. 2017-03-29. Negative bulk modulus and possibility of loss of elastic stability near tricritical transitions in thin films on substrates. https://doi.org/10.1080/00150193.2016.1236608

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