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Revival of the spin-Peierls transition in Cu_xZn_(1-x)GeO_3 under pressure

M. Fischer·P. H. M. van Loosdrecht·P. Lemmens·G. Güntherodt·B. Büchner·T. Lorenz·M. Breuer·J. Zeman·G. Martinez·G. Dhalenne·A. Revcolevschi
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Abstract

Pressure and temperature dependent susceptibility and Raman scattering experiments on single crystalline Cu_xZn_(1-x)GeO_3 have shown an unusually strong increase of the spin-Peierls phase transition temperature upon applying hydrostatic pressure. The large positive pressure coefficient (7.5 K/GPa) - almost twice as large as for the pure compound (4.5 K/GPa) - is interpreted as arising due to an increasing magnetic frustration which decreases the spin-spin correlation length, and thereby weakens the influence of the non-magnetic Zn-substitution.

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M. Fischer, P. H. M. van Loosdrecht, P. Lemmens, G. Güntherodt, B. Büchner, T. Lorenz, M. Breuer, J. Zeman, G. Martinez, G. Dhalenne, A. Revcolevschi. 1997-12-12. Revival of the spin-Peierls transition in Cu_xZn_(1-x)GeO_3 under pressure. https://doi.org/10.1103/physrevb.57.7749

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