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Elastic Behavior of a Two-dimensional Crystal near Melting

H. H. von Grünberg·P. Keim·K. Zahn·G. Maret
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Abstract

Using positional data from video-microscopy we determine the elastic moduli of two-dimensional colloidal crystals as a function of temperature. The moduli are extracted from the wave-vector-dependent normal mode spring constants in the limit $q\to 0$ and are compared to the renormalized Young's modulus of the KTHNY theory. An essential element of this theory is the universal prediction that Young's modulus must approach $16 π$ at the melting temperature. This is indeed observed in our experiment.

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H. H. von Grünberg, P. Keim, K. Zahn, G. Maret. 2004-07-05. Elastic Behavior of a Two-dimensional Crystal near Melting. https://doi.org/10.1103/physrevlett.93.255703

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