Abstract
The widely used double-exchange model for manganites is shown to support various “striped” phases at filling fractions 1/n (n = 3, 4, 5, . . .), in the previously unexplored regime of narrow bandwidth and small Jahn-Teller coupling. Working in two dimensions, our main result is that these stripes can be individually spin flipped without a physically relevant change in the energy, i.e., we find a large ground-state manifold with nearly degenerate energies. The two-dimensional spin system thus displays an unexpected dynamically generated dimensional reduction into decoupled one-dimensional stripes, even though the electronic states remain two dimensional. Relations of our results with recent literature addressing compass models in quantum computing are discussed.
