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Enhanced magnetic fluctuations in doped spin-Peierls systems: a single-chain model analysis

M. Fabrizio·R. Mélin
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Abstract

We analyze by means of real space Renormalization Group (RG) as well as by exact diagonalizations the properties of a single-chain model of a doped spin-Peierls system, where a major role is played by the localized moments created by the impurities. We are able to follow analytically the RG flow, which allows us to determine the relevant cross-over temperatures. In particular, we find an enhancement of magnetic correlations due to disorder, coexisting with an underlying dimerization, in an intermediate temperature range below the spin-Peierls critical temperature and above the coherence temperature of a regular array built by those localized moments (so-called soliton bandwidth). The possible relevance of these results to the doped inorganic spin-Peierls compound CuGeO$_3$ is discussed.

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M. Fabrizio, R. Mélin. 1997-03-19. Enhanced magnetic fluctuations in doped spin-Peierls systems: a single-chain model analysis. https://doi.org/10.1103/physrevb.56.5996

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