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arXiv · 1109.2410

Spin Excitation Assisted by Non-Softening Phonon for Spin-Peierls Model

Takanori Sugimoto·Shigetoshi Sota·Takami Tohyama
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Abstract

We study spin dynamics of a spin-Peierls chain with nearest-neighbor and next-nearest-neighbor Heisenberg spin exchange interactions together with a gapped and dispersionless phonon. The dynamical spin correlation function and phonon excitation spectrum are calculated at zero temperature by using dynamical density-matrix renormalization-group method. We find a new spin excitation assisted by non-softening phonon. The excitation is located above phonon in energy and shows a dispersive feature with strong intensity near the momentum $π$. The phonon excitation spectrum is also influenced by the spin-phonon interaction. We discuss the possibility of observing the spin-phonon coupled features in inorganic spin-Peierls compound CuGeO$_3$.

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Takanori Sugimoto, Shigetoshi Sota, Takami Tohyama. 2011-12-02. Spin Excitation Assisted by Non-Softening Phonon for Spin-Peierls Model. https://doi.org/10.1143/jpsj.81.034706

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