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Landau Theory of Stripe Phases in Cuprates and Nickelates

Oron Zachar·S. A. Kivelson·V. J. Emery
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Abstract

We consider a Landau theory of coupled charge and spin-density wave order parameters as a simple model for the ordering that has been observed experimentally in the La_2NiO_4 and La_2CuO_4 families of doped antiferromagnets. The period of the charge-density wave is generically half that of the spin-density wave, or equivalently the charges form antiphase domain walls in the antiferromagnetic order. A sharp distinction exists between the case in which the ordering is primarily charge driven (which produces a sequence of transitions in qualitative agreement with experiment) or spin driven (which does not). We also find that stripes with non-collinear spin order (i.e. spiral phases) are possible in a region of the phase diagram where the transition is spin driven; the spiral is circular only when there is no charge order, and is otherwise elliptical with an eccentricity proportional to the magnitude of the charge order.

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Oron Zachar, S. A. Kivelson, V. J. Emery. 1997-02-05. Landau Theory of Stripe Phases in Cuprates and Nickelates. https://doi.org/10.1103/physrevb.57.1422

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