Ferromagnetic and antiferromagnetic order in bacterial vortex lattices
| dc.contributor.author | Wioland, Hugo | |
| dc.contributor.author | Dunkel, Jörn | |
| dc.date.accessioned | 2019-04-26T08:56:55Z | |
| dc.date.available | 2019-04-26T08:56:55Z | |
| dc.date.issued | 04/01/16 | |
| dc.description | Despite their inherently non-equilibrium nature [1] , living systems can self-organize in highly ordered collective states [2,3] that share striking similarities with the thermodynamic equilibrium phases [4,5] of conventional condensed-matter and fluid systems. Examples range from the liquid-crystal-like arrangements of bacterial colonies [6,7], microbial suspensions [8,9] and tissues [10] to the coherent macro-scale dynamics in schools of fish [11] and flocks of birds [12]. Yet, the generic mathematical principles that govern the emergence of structure in such artificial [13] and biological [6–9,14] systems are elusive. It is not clear when, or even whether, well-established theoretical concepts describing universal thermostatistics of equilibrium systems can capture and classify ordered states of living matter. Here, we connect these two previously disparate regimes: through microfluidic experiments and mathematical modelling, we demonstrate that lattices of hydrodynamically coupled bacterial vortices can spontaneously organize into distinct patterns characterized by ferro- and antiferromagnetic order. The coupling between adjacent vortices can be controlled by tuning the inter-cavity gap widths. The emergence of opposing order regimes is tightly linked to the existence of geometry-induced edge currents [15,16], reminiscent of those in quantum systems [17–19]. Our experimental observations can be rationalized in terms of a generic lattice field theory, suggesting that bacterial spin networks belong to the same universality class as a wide range of equilibrium systems. | |
| dc.identifier.uri | https://dspace7-entities.atmire.com/handle/atmire/436 | |
| dc.language | en | |
| dc.publisher | Nature Publishing Group | |
| dc.title | Ferromagnetic and antiferromagnetic order in bacterial vortex lattices |