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Microphase Separation and modulated phases in a Coulomb frustrated Ising ferromagnet

P. Viot·G. Tarjus
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Abstract

We study a 3-dimensional Ising model in which the tendency to order due to short-range ferromagnetic interactions is frustrated by competing long-range (Coulombic) interactions. Complete ferromagnetic ordering is impossible for any nonzero value of the frustration parameter, but the system displays a variety of phases characterized by periodically modulated structures. We have performed extensive Monte-Carlo simulations which provide strong evidence that the microphase separation transition between paramagnetic and modulated phases is a fluctuation-induced first-order transition. Additional transitions to various commensurate phases may also occur when further lowering the temperature.

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P. Viot, G. Tarjus. 1998-09-18. Microphase Separation and modulated phases in a Coulomb frustrated Ising ferromagnet. https://doi.org/10.1209/epl%2Fi1998-00489-5

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