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Magnetic excitations in a bond-centered stripe phase: Spin waves far from the semi-classical limit

Matthias Vojta·Tobias Ulbricht
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Abstract

Using a spin-only model, we compute spin excitation spectra in a bond-centered stripe state with long-range magnetic order. We employ a bond operator formalism, which naturally captures both dimerization and broken spin symmetry in a unified framework. At low energies, the spin excitations resemble spin waves, but at higher energies they are very similar to spin-1 excitations of isolated spin ladders. Our theory does well describe neutron scattering data [J. M. Tranquada et al., Nature 429, 534 (2004)] on LaBaCuO, pointing towards bond order in this material.

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Matthias Vojta, Tobias Ulbricht. 2004-09-17. Magnetic excitations in a bond-centered stripe phase: Spin waves far from the semi-classical limit. https://doi.org/10.1103/physrevlett.93.127002

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