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Fluctuating Topological Defects in 2D Liquids: Heterogeneous Motion and Noise

C. Reichhardt·C. J. Olson Reichhardt
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Abstract

We measure the defect density as a function of time at different temperatures in simulations of a two dimensional system of interacting particles. Just above the solid to liquid transition temperature, the power spectrum of the defect fluctuations shows a 1/f signature, which crosses over to a white noise signature at higher temperatures. When 1/f noise is present, the 5-7 defects predominately form string like structures, and the particle trajectories show a 1D correlated motion that follows the defect strings. At higher temperatures this heterogeneous motion is lost. We demonstrate this heterogeneity both in systems interacting with a short ranged screened Coulomb interaction, as well as in systems with a long range logarithmic interaction between the particles.

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C. Reichhardt, C. J. Olson Reichhardt. 2002-09-14. Fluctuating Topological Defects in 2D Liquids: Heterogeneous Motion and Noise. https://doi.org/10.1103/physrevlett.90.095504

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