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arXiv · 1603.00070

Emergent interacting spin islands in a depleted strong-leg Heisenberg ladder

D. Schmidiger·K. Yu. Povarov·S. Galeski·N. Reynolds·R. Bewley·T. Guidi·J. Ollivier·A. Zheludev
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Abstract

Properties of the depleted Heisenberg spin ladder material series (C$_7$H$_{10}$N)$_2$Cu$_{1-z}$Zn$_{z}$Br$_4$ have been studied by the combination of magnetic measurements and neutron spectroscopy. Disorder-induced degrees of freedom lead to a specific magnetic response, described in terms of emergent strongly interacting "spin island" objects. The structure and dynamics of the spin islands is studied by high-resolution inelastic neutron scattering. This allows to determine their spatial shape and to observe their mutual interactions, manifested by strong spectral in-gap contributions.

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D. Schmidiger, K. Yu. Povarov, S. Galeski, N. Reynolds, R. Bewley, T. Guidi, J. Ollivier, A. Zheludev. 2016-02-29. Emergent interacting spin islands in a depleted strong-leg Heisenberg ladder. https://doi.org/10.1103/physrevlett.116.257203

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