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arXiv · 1605.07087

Direct evidence for charge stripes in a layered cobalt oxide

P. Babkevich·P. G. Freeman·M. Enderle·D. Prabhakaran·A. T. Boothroyd
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Abstract

Recent experiments indicate that static stripe-like charge order is generic to the hole-doped copper oxide superconductors and competes with superconductivity. Here we show that a similar type of charge order is present in La$_{5/3}$Sr$_{1/3}$CoO$_4$, an insulating analogue of the copper oxide superconductors containing cobalt in place of copper. The stripe phase we have detected is accompanied by short-range, quasi-one-dimensional, antiferromagnetic order, and provides a natural explanation for the distinctive hourglass shape of the magnetic spectrum previously observed in neutron scattering measurements of La$_{5/3}$Sr$_{1/3}$CoO$_4$ and many hole-doped copper oxide superconductors. The results establish a solid empirical basis for theories of the hourglass spectrum built on short-range, quasi-static, stripe correlations.

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P. Babkevich, P. G. Freeman, M. Enderle, D. Prabhakaran, A. T. Boothroyd. 2016-05-23. Direct evidence for charge stripes in a layered cobalt oxide. https://doi.org/10.1038/ncomms11632

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