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Cooperative ordering of gapped and gapless spin networks in Cu$_2$Fe$_2$Ge$_4$O$_{13}$

T. Masuda·A. Zheludev·B. Grenier·S. Imai·K. Uchinokura·E. Ressouche·S. Park
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Abstract

The unusual magnetic properties of a novel low-dimensional quantum ferrimagnet Cu$_2$Fe$_2$Ge$_4$O$_{13}$ are studied using bulk methods, neutron diffraction and inelastic neutron scattering. It is shown that this material can be described in terms of two low-dimensional quantum spin subsystems, one gapped and the other gapless, characterized by two distinct energy scales. Long-range magnetic ordering observed at low temperatures is a cooperative phenomenon caused by weak coupling of these two spin networks.

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T. Masuda, A. Zheludev, B. Grenier, S. Imai, K. Uchinokura, E. Ressouche, S. Park. 2004-04-20. Cooperative ordering of gapped and gapless spin networks in Cu$_2$Fe$_2$Ge$_4$O$_{13}$. https://doi.org/10.1103/physrevlett.93.077202

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