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arXiv · 1603.04090

Magnetic ordering in the ultra-pure site-diluted spin chain materials SrCu$_{1-x}$Ni$_x$O$_2$

G. Simutis·M. Thede·R. Saint-Martin·A. Mohan·C. Baines·Z. Guguchia·R. Khasanov·C. Hess·A. Revcolevschi·B. Buchner·A. Zheludev
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Abstract

Muon spin rotation technique is used to study magnetic ordering in ultra-pure samples of SrCu$_{1-x}$Ni$_x$O$_2$, an archetypical $S=1/2$ antiferromagnetic Heisenberg chain system with a small amount of $S=1$ defects. The ordered state in the parent compound is shown to be highly homogeneous, contrary to previous report [M. Matsuda et al., Phys. Rev. B \textbf{55}, R11953 (1997)]. Even minute amount of Ni impurities result in inhomogeneous order and a decrease of the transition temperature. At as little as $0.5$~\% Ni concentration, magnetic ordering is entirely suppressed. The results are compared to previous theoretical studies of weakly coupled spin chains with site-defects.

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G. Simutis, M. Thede, R. Saint-Martin, A. Mohan, C. Baines, Z. Guguchia, R. Khasanov, C. Hess, A. Revcolevschi, B. Buchner, A. Zheludev. 2016-03-13. Magnetic ordering in the ultra-pure site-diluted spin chain materials SrCu$_{1-x}$Ni$_x$O$_2$. https://doi.org/10.1103/physrevb.93.214430

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