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Structural Critical Scattering Study of Mg-Doped CuGeO3

Y. J. Wang·V. Kiryukhin·R. J. Birgeneau·T. Masuda·I. Tsukada·K. Uchinokura
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Abstract

We report a synchrotron x-ray scattering study of the diluted spin-Peierls (SP) material Cu_(1-x)Mg_xGeO_3. We find that for x>0 the temperature T_m at which the spin gap is established is significantly higher than the temperature T_s at which the SP dimerization attains long-range order. The latter is observed only for x x_c the SP correlation length quickly decreases with increasing x. We argue that impurity-induced competing interactions play a central role in these phenomena.

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Y. J. Wang, V. Kiryukhin, R. J. Birgeneau, T. Masuda, I. Tsukada, K. Uchinokura. 1999-07-20. Structural Critical Scattering Study of Mg-Doped CuGeO3. https://doi.org/10.1103/physrevlett.83.1676

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