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Lattice Dimerization in the Spin-Peierls Compound CuGeO$_3$

B. Büchner·H. Fehske·A. P. Kampf·G. Wellein
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Abstract

The uniaxial pressure dependences of the exchange coupling and the structural distortion in the dimerized phase of CuGeO$_3$ are analyzed. A minimum magnetic dimerization of 3 % is obtained, incompatible with an adiabatic approach to the spin-Peierls transition. Exploring the properties of an Heisenberg spin chain with dynamical spin-phonon coupling, the dimerization dependence of the spin excitation gap is found to be in qualitative agreement with experiment.

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B. Büchner, H. Fehske, A. P. Kampf, G. Wellein. 1998-06-02. Lattice Dimerization in the Spin-Peierls Compound CuGeO$_3$. https://doi.org/10.1016/s0921-4526(98)00720-0

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