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Direct evidence for charge stripes in a layered cobalt oxide.

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 La5/3Sr1/3CoO4, 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 La2-xSrxCoO4 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.

SUBMITTER: Babkevich P

PROVIDER: S-EPMC4879241 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Direct evidence for charge stripes in a layered cobalt oxide.

Babkevich P P Freeman P G PG Enderle M M Prabhakaran D D Boothroyd A T AT

Nature communications 20160523

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 La5/3Sr1/3CoO4, 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 distinct ...[more]

PMID: 27212023

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