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arXiv · 2206.13566

Collisions enhance self-diffusion in odd-diffusive systems

Erik Kalz·Hidde Derk Vuijk·Iman Abdoli·Jens-Uwe Sommer·Hartmut Löwen·Abhinav Sharma
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Abstract

It is generally believed that collisions of particles reduce the self-diffusion coefficient. Here we show that in odd-diffusive systems, which are characterized by diffusion tensors with antisymmetric elements, collisions surprisingly can enhance the self-diffusion. In these systems, due to an inherent curving effect, the motion of particles is facilitated, instead of hindered by collisions leading to a mutual rolling effect. Using a geometric model, we analytically predict the enhancement of the self-diffusion coefficient with increasing density. This counterintuitive behaviour is demonstrated in the archetypal odd-diffusive system of Brownian particles under Lorentz force. We validate our findings by many body Brownian dynamics simulations in dilute systems.

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Erik Kalz, Hidde Derk Vuijk, Iman Abdoli, Jens-Uwe Sommer, Hartmut Löwen, Abhinav Sharma. 2022-06-27. Collisions enhance self-diffusion in odd-diffusive systems. https://doi.org/10.1103/physrevlett.129.090601

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