Heterogeneous response and non-Markovianity in the microrheology of semisolid viscoelastic materials

T. N. Azevedo; L. G. Rizzi

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arXiv · 2506.05311

Heterogeneous response and non-Markovianity in the microrheology of semisolid viscoelastic materials

T. N. Azevedo·L. G. Rizzi

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Abstract

Recent works indicate that heterogeneous response and non-Markovianity may yield recognizable hallmarks in the microrheology of semisolid viscoelastic materials. Here we perform numerical simulations using a non-Markovian overdamped Langevin approach to explore how the microrheology experienced by probe particles immersed in an effective semisolid material can be influenced by its micro-heterogeneities. Our results show that, besides affecting the mean squared displacement, the time-dependent diffusion coefficient, and the shear moduli, the micro-heterogeneities lead to displacement distributions that deviate from the usual Gaussian behavior. In addition, our study provides an analytical way to characterize the micro-heterogeneities of semisolid viscoelastic materials through their microrheology.

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T. N. Azevedo, L. G. Rizzi. 2025-06-05. Heterogeneous response and non-Markovianity in the microrheology of semisolid viscoelastic materials. https://arxiv.org/abs/2506.05311

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