Two-stage Slowdown of Vacancy-mediated Diffusion in a Lattice Gas Model with Quenched Disorder and Spins

Qiang Zhai

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arXiv · 2610.29931

Two-stage Slowdown of Vacancy-mediated Diffusion in a Lattice Gas Model with Quenched Disorder and Spins

Qiang Zhai

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Abstract

We present a lattice gas model with random interactions quenched in space and spins quenched to the particles. The vacancy-mediated diffusion is studied in equilibrium. A two-stage slowdown is witnessed in both the mean squared displacement and the spatial overlaps. We demonstrate that the plateaus are due to anti-correlation at the corresponding length scale. The anti-correlation diminishes quickly with increasing lag time. A broad and yet finite distribution of the survival function of vacancies suggests their normal diffusion at large time limit. Our model can serve as a new playground for understanding hierarchical dynamics in glassy-like dynamical systems.

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Qiang Zhai. 2026-10-21. Two-stage Slowdown of Vacancy-mediated Diffusion in a Lattice Gas Model with Quenched Disorder and Spins. https://arxiv.org/abs/2610.29931

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