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Two-magnon Raman scattering in spin-ladders with exact singlet-rung ground state

P. N. Bibikov
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Abstract

We suggest a family of spin-ladder models with exact singlet-rung vacuum. In addition to the terms describing interactions along legs and rungs the Hamiltonian has frustration and cyclic terms. Using coordinate Bethe ansatze all one- and two-dimensional states are constructed. The explicit formula for zero-temperature Raman scattering cross section is derived. The corresponding line-shapes are strongly asymmetric and have no more than one van-Hove singularity. The results are in good agreement with experimental data.

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P. N. Bibikov. 2005-08-10. Two-magnon Raman scattering in spin-ladders with exact singlet-rung ground state. https://doi.org/10.1103/physrevb.72.012416

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