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Magneto-elastic excitations in spin-Peierls systems

Michael Holicki·Holger Fehske·Ralph Werner
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Abstract

Within the random phase approximation to the spin-Peierls transition two parameter regimes of phonon softening and hardening are present. Magneto-elastic excitations are discussed in detail for phonons coupled to the exactly solvable model of XY spin chains for both regimes, leading to a modified interpretation of the 30 cm$^{-1}$ mode in CuGeO$_3$. Frustrated Heisenberg chains coupled to phonons satisfactory describe the pre-transitional quasi-elastic scattering in CuGeO$_3$. A real space interpretation of the quasi-elastic scattering is given justifying effective Ising model approaches.

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Michael Holicki, Holger Fehske, Ralph Werner. 2000-06-09. Magneto-elastic excitations in spin-Peierls systems. https://doi.org/10.1103/physrevb.63.174417

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