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arXiv · 1412.7945

Observation of Devil's Staircase in the Novel Spin Valve System SrCo$_6$O$_{11}$

T. Matsuda·S. Partzsch·T. Tsuyama·E. Schierle·E. Weschke·J. Geck·T. Saito·S. Ishiwata·Y. Tokura·H. Wadati
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Abstract

Using resonant soft x-ray scattering as a function of both temperature and magnetic field, we reveal a large number of almost degenerate magnetic orders in SrCo6O11. The Ising-like spins in this frustrated material in fact exhibit a so-called magnetic devil's staircase. It is demonstrated how a magnetic field induces transitions between different microscopic spin configurations, which is responsible for the magnetoresistance of SrCo6O11. This material therefore constitutes a unique combination of a magnetic devil's staircase and spin valve effects, yielding a novel type of magnetoresistance system.

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T. Matsuda, S. Partzsch, T. Tsuyama, E. Schierle, E. Weschke, J. Geck, T. Saito, S. Ishiwata, Y. Tokura, H. Wadati. 2014-12-26. Observation of Devil's Staircase in the Novel Spin Valve System SrCo$_6$O$_{11}$. https://doi.org/10.1103/physrevlett.114.236403

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