Susceptibility of Polar Flocks to Spatial Anisotropy
arXiv:2201.00704 · doi:10.1103/PhysRevLett.128.208004
Abstract
We consider the effect of spatial anisotropy on polar flocks by investigating active -state clock models in two dimensions. In contrast to what happens in equilibrium, we find that, in the large-size limit, any amount of anisotropy changes drastically the phenomenology of the rotationally-invariant case, destroying long-range correlations, pinning the direction of global order, and transforming the traveling bands of the coexistence phase into a single moving domain. All this happens beyond a lengthscale that diverges in the limit. A phenomenology akin to that of the Vicsek model can thus be observed in a finite system for large enough values of . We provide a scaling argument which rationalizes why anisotropy has so different effects in the passive and active cases.
arXiv comment6 pages with 4 figures. 4 pages of supplementary information (as ancillary file)
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