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Magnetic Excitations in the Spin-Peierls System $CuGeO_3$

G. Bouzerar·A. P. Kampf·F. Schönfeld
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Abstract

We have calculated the magnetic excitation spectrum in frustrated and dimerized spin 1/2 Heisenberg chains for model parameters which describe the thermodynamics and low frequency spin dynamics in the spin--Peierls system $CuGeO_{3}$. As a test the chosen model is found to reproduce the lowest Raman excitation energy near $30 cm^{-1}$ in the dimerized phase. We establish the elementary triplet and singlet excitation branches below the continuum and estimate the interchain coupling effects on the dimerization parameter.

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G. Bouzerar, A. P. Kampf, F. Schönfeld. 1997-01-23. Magnetic Excitations in the Spin-Peierls System $CuGeO_3$. https://arxiv.org/abs/cond-mat/9701176

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