Truncated correlations in video microscopy of colloidal solids

Michael Schindler; A. C. Maggs

doi:10.1039/c2sm07117g

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arXiv · 1111.1419

Truncated correlations in video microscopy of colloidal solids

Michael Schindler·A. C. Maggs

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Abstract

Studies by video microscopy on fluctuating colloids measure the real-space cross-correlations in particle motion. This set of correlations is then treated as a matrix, in order to study the spectrum and mode structure. We show that in general the modes are modified by the truncation of the full real-space correlations. We perform a theoretical analysis of the truncation, find the boundary conditions imposed by the truncation, and propose practical windowing strategies to eliminate artefacts. We study the problem from various perspectives, to compile a survey for experimentalists.

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Michael Schindler, A. C. Maggs. 2011-11-06. Truncated correlations in video microscopy of colloidal solids. https://doi.org/10.1039/c2sm07117g

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