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arXiv · 1009.3122

Evidence for site-centered stripes from magnetic excitations in CuO superconductors

Martin Greiter·Holger Schmidt
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Abstract

The success of models of coupled two-leg spin ladders in describing the magnetic excitation spectrum of La_[2-x]Ba_xCuO_4 has been widely interpreted as evidence for bond-centered stripes. Here, we determine the magnetic coupling induced by the charge stripes between bond- or site-centered spin stripes modeled by two- or three-leg ladders, respectively. We find that only the site-centered models order. We further report excellent agreement of a fully consistent analysis of coupled three-leg ladders using a spin wave theory of bond operators with the experiment.

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Martin Greiter, Holger Schmidt. 2010-09-16. Evidence for site-centered stripes from magnetic excitations in CuO superconductors. https://doi.org/10.1103/physrevb.82.144512

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