Electronic superlattice revealed by resonant scattering from random impurities in Sr3Ru2O7

M. A. Hossain; I. Zegkinoglou; Y. -D. Chuang; J. Geck; B. Bohnenbuck; A. G. Cruz Gonzalez; H. -H. Wu; C. Schussler-Langeheine; D. G. Hawthorn; J. D. Denlinger; R. Mathieu; Y. Tokura; S. Satow; H. Takagi; Y. Yoshida; Z. Hussain; B. Keimer; G. A. Sawatzky; A. Damascelli

doi:10.1038/srep02299

arXiv · 1308.0185

Electronic superlattice revealed by resonant scattering from random impurities in Sr3Ru2O7

M. A. Hossain·I. Zegkinoglou·Y. -D. Chuang·J. Geck·B. Bohnenbuck·A. G. Cruz Gonzalez·H. -H. Wu·C. Schussler-Langeheine·D. G. Hawthorn·J. D. Denlinger·R. Mathieu·Y. Tokura·S. Satow·H. Takagi·Y. Yoshida·Z. Hussain·B. Keimer·G. A. Sawatzky·A. Damascelli

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Abstract

Resonant elastic x-ray scattering (REXS) is an exquisite element-sensitive tool for the study of subtle charge, orbital, and spin superlattice orders driven by the valence electrons, which therefore escape detection in conventional x-ray diffraction (XRD). Although the power of REXS has been demonstrated by numerous studies of complex oxides performed in the soft x-ray regime, the cross section and photon wavelength of the material-specific elemental absorption edges ultimately set the limit to the smallest superlattice amplitude and periodicity one can probe. Here we show -- with simulations and REXS on Mn-substituted Sr$_3$Ru$_2$O$_7$ -- that these limitations can be overcome by performing resonant scattering experiments at the absorption edge of a suitably-chosen, dilute impurity. This establishes that -- in analogy with impurity-based methods used in electron-spin-resonance, nuclear-magnetic resonance, and Mössbauer spectroscopy -- randomly distributed impurities can serve as a non-invasive, but now momentum-dependent probe, greatly extending the applicability of resonant x-ray scattering techniques.

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M. A. Hossain, I. Zegkinoglou, Y. -D. Chuang, J. Geck, B. Bohnenbuck, A. G. Cruz Gonzalez, H. -H. Wu, C. Schussler-Langeheine, D. G. Hawthorn, J. D. Denlinger, R. Mathieu, Y. Tokura, S. Satow, H. Takagi, Y. Yoshida, Z. Hussain, B. Keimer, G. A. Sawatzky, A. Damascelli. 2013-08-01. Electronic superlattice revealed by resonant scattering from random impurities in Sr3Ru2O7. https://doi.org/10.1038/srep02299

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