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Driven Heisenberg Magnets: Nonequilibrium Criticality, Spatiotemporal Chaos and Control

Jayajit Das·Madan Rao·Sriram Ramaswamy
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Abstract

We drive a $d$-dimensional Heisenberg magnet using an anisotropic current. The continuum Langevin equation is analysed using a dynamical renormalization group and numerical simulations. We discover a rich steady-state phase diagram, including a critical point in a new nonequilibrium universality class, and a spatiotemporally chaotic phase. The latter may be `controlled' in a robust manner to target spatially periodic steady states with helical order.

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Jayajit Das, Madan Rao, Sriram Ramaswamy. 2002-12-03. Driven Heisenberg Magnets: Nonequilibrium Criticality, Spatiotemporal Chaos and Control. https://doi.org/10.1209/epl%2Fi2002-00280-2

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