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Harmonic lattice behavior of two-dimensional colloidal crystals

P. Keim·G. Maret·U. Herz·H. H. von Grünberg
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Abstract

Using positional data from video-microscopy and applying the equipartition theorem for harmonic Hamiltonians, we determine the wave-vector-dependent normal mode spring constants of a two-dimensional colloidal model crystal and compare the measured band-structure to predictions of the harmonic lattice theory. We find good agreement for both the transversal and the longitudinal mode. For $q\to 0$, the measured spring constants are consistent with the elastic moduli of the crystal.

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P. Keim, G. Maret, U. Herz, H. H. von Grünberg. 2004-02-17. Harmonic lattice behavior of two-dimensional colloidal crystals. https://doi.org/10.1103/physrevlett.92.215504

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