Electronic and magnetic nano phase separation in cobaltates La$_{2-x}$Sr$_{x}$CoO$_4$

Z. W. Li; Y. Drees; A. Ricci; D. Lamago; A. Piovano; M. Rotter; W. Schmidt; O. Sobolev; U. Rütt; O. Gutowski; M. Sprung; J. P. Castellan; L. H. Tjeng; A. C. Komarek

arXiv · 1601.01795

Electronic and magnetic nano phase separation in cobaltates La$_{2-x}$Sr$_{x}$CoO$_4$

Z. W. Li·Y. Drees·A. Ricci·D. Lamago·A. Piovano·M. Rotter·W. Schmidt·O. Sobolev·U. Rütt·O. Gutowski·M. Sprung·J. P. Castellan·L. H. Tjeng·A. C. Komarek

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Abstract

The single-layer perovskite cobaltates have attracted enormous attention due to the recent observation of hour-glass shaped magnetic excitation spectra which resemble the ones of the famous high-temperature superconducting cuprates. Here, we present an overview of our most recent studies of the spin and charge correlations in floating-zone grown cobaltate single crystals. We find that frustration and a novel kind of electronic and magnetic nano phase separation are intimately connected to the appearance of the hour-glass shaped spin excitation spectra. We also point out the difference between nano phase separation and conventional phase separation.

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Z. W. Li, Y. Drees, A. Ricci, D. Lamago, A. Piovano, M. Rotter, W. Schmidt, O. Sobolev, U. Rütt, O. Gutowski, M. Sprung, J. P. Castellan, L. H. Tjeng, A. C. Komarek. 2016-01-08. Electronic and magnetic nano phase separation in cobaltates La$_{2-x}$Sr$_{x}$CoO$_4$. https://arxiv.org/abs/1601.01795

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