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arXiv · 2303.08223

Inertial Spinner Swarm Experiments: Spin Pumping, Entropy Oscillations and Spin Frustration

Shengkai Li·Trung V. Phan·Gao Wang·Ramzi R. Khuri·Robert H. Austin·Liyu Liu
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Abstract

We present here an inertial active spinning swarm consisting of mixtures of opposite handedness torque driven spinners floating on an air bed with low damping. Depending on the relative spin sign, spinners can act as their own anti-particles and annihilate their spins. Rotational energy can become highly focused, with minority fraction spinners pumped to very high levels of spin angular momentum. Spinner handedness also matters at high spinner densities but not low densities: oscillations in the mixing spatial entropy of spinners over time emerge if there is a net spin imbalance from collective rotations. Geometrically confined spinners can lock themselves into frustrated spin states.

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Shengkai Li, Trung V. Phan, Gao Wang, Ramzi R. Khuri, Robert H. Austin, Liyu Liu. 2023-03-14. Inertial Spinner Swarm Experiments: Spin Pumping, Entropy Oscillations and Spin Frustration. https://doi.org/10.1038/s42005-024-01619-4

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