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Double-Exchange Model: Phase Diagram at Zero-Temperature

David Pekker·Swagatam Mukhopadhyay·Nandini Trivedi·Paul M. Goldbart
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Abstract

The analytical zero-temperature phase diagram of the double exchange model for classical background spins as a function of the carrier density and Hund's coupling in the entire range of these parameters is presented. By constructing a continuum field theory we explore the possibility of a continuous phase transition from ferromagnetic state to a gently varying textured state. We find such a transition in and below two dimensions and show that the emerging stable state is a spin-spiral which survives the tendency towards phase separation into commonly considered phases, and is also energetically favored to the canted state, for low carrier density.

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David Pekker, Swagatam Mukhopadhyay, Nandini Trivedi, Paul M. Goldbart. 2005-02-25. Double-Exchange Model: Phase Diagram at Zero-Temperature. https://arxiv.org/abs/cond-mat/0502621

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