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arXiv · 2105.14535

Alignment Destabilizes Crystal Orders in Active Systems

Chen Huang·Leiming Chen·Xiangjun Xing
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Abstract

We combine numerical and analytical methods to study two dimensional active crystals formed by permanently linked swimmers and with two distinct alignment interactions. The system admits a stationary phase with quasi long range translational order, as well as a moving phase with quasi-long range velocity order. The translational order in the moving phase is significantly influenced by alignment interaction. For Vicsek-like alignment, the translational order is short-ranged, whereas the bond-orientational order is quasi-long ranged, implying a moving hexatic phase. For elasticity-based alignment, the translational order is quasi-long ranged parallel to the motion and short-ranged in perpendicular direction, whereas the bond orientational order is long-ranged. We also generalize these results to higher dimensions.

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Chen Huang, Leiming Chen, Xiangjun Xing. 2021-05-30. Alignment Destabilizes Crystal Orders in Active Systems. https://doi.org/10.1103/physreve.104.064605

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