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Crystalline phases in chiral ferromagnets: Destabilization of helical order

I. Fischer·N. Shah·A. Rosch
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Abstract

In chiral ferromagnets, weak spin-orbit interactions twist the ferromagnetic order into spirals, leading to helical order. We investigate an extended Ginzburg-Landau theory of such systems where the helical order is destabilized in favor of crystalline phases. These crystalline phases are based on periodic arrangements of double-twist cylinders and are strongly reminiscent of blue phases in liquid crystals. We discuss the relevance of such blue phases for the phase diagram of the chiral ferromagnet MnSi.

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I. Fischer, N. Shah, A. Rosch. 2008-04-11. Crystalline phases in chiral ferromagnets: Destabilization of helical order. https://doi.org/10.1103/physrevb.77.024415

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