Phase diagram for Coulomb-frustrated phase separation in systems with negative short-range compressibility

C. Ortix; J. Lorenzana; C. Di Castro

doi:10.1103/physrevlett.100.246402

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arXiv · 0801.0955

Phase diagram for Coulomb-frustrated phase separation in systems with negative short-range compressibility

C. Ortix·J. Lorenzana·C. Di Castro

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Abstract

Using numerical techniques and asymptotic expansions we obtain the phase diagram of a paradigmatic model of Coulomb frustrated phase separation in systems with negative short-range compressibility. The transition from the homogeneous phase to the inhomogeneous phase is generically first order in isotropic three-dimensional systems except for a critical point. Close to the critical point, inhomogeneities are predicted to form a BCC lattice with subsequent transitions to a triangular lattice of rods and a layered structure. Inclusion of a strong anisotropy allows for second- and first-order transition lines joined by a tricritical point.

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C. Ortix, J. Lorenzana, C. Di Castro. 2008-04-23. Phase diagram for Coulomb-frustrated phase separation in systems with negative short-range compressibility. https://doi.org/10.1103/physrevlett.100.246402

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