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arXiv · 2103.15775

Translational Dynamics of Rod-like Particles in Supercooled Liquids: Probing Dynamic Heterogeneity and Amorphous Order

Anoop Mutneja·Smarajit Karmakar
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Abstract

The use of probe molecules to extract the local dynamical and structural properties of complex dynamical systems is an age-old technique both in simulations and experiments. A lot of important information which is not immediately accessible from the bulk measurements can be accessed via these local measurements. Still, a detailed understanding of how a probe particle's dynamics are affected by the surrounding liquid medium is not very well understood, especially in the supercooled temperature regime. This work shows how translational dynamics of a rod-like particle immersed in a supercooled liquid can give us information on the growth of the correlation length scale associated with dynamical heterogeneity and the multi-body static correlations in the medium. A unified scaling theory rationalizes all the observed results leading to the development of a novel yet simple method that is accessible in experiments to measure the growth of these important length-scales in molecular glass-forming liquids.

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Anoop Mutneja, Smarajit Karmakar. 2021-03-29. Translational Dynamics of Rod-like Particles in Supercooled Liquids: Probing Dynamic Heterogeneity and Amorphous Order. https://arxiv.org/abs/2103.15775

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