Local Noncentrosymmetric Structure of Bi2Sr2CaCu2O8+y by X-ray Magnetic Circular Dichroism at Cu K-Edge XANES

  • Andrey A. IvanovEmail author
  • Valentin G. Ivanov
  • Alexey P. Menushenkov
  • Fabrice Wilhelm
  • Andrei Rogalev
  • Alessandro Puri
  • Boby Joseph
  • Wei Xu
  • Augusto Marcelli
  • Antonio Bianconi
Original Paper


The two-dimensional Bi2Sr2CaCu2O8+y (Bi2212), the most studied prototype cuprate superconductor, is a lamellar system made of a stack of two-dimensional corrugated CuO2 bilayers separated by Bi2O2 + y Sr2 O2 layers. While the large majority of theories, proposed to interpret unconventional high T c superconductivity in Bi2Sr2CaCu2O8+y , assume a centrosymmetric tetragonal CuO2 lattice for the [CuO2]Ca[CuO2] bilayer, here, we report new compelling results providing evidence for local noncentrosymmetric symmetry at the Cu atom. We have measured polarized Cu K-edge XANES (X-ray absorption near-edge structure) and the K-edge X-ray magnetic circular dichroism (XMCD) of a Bi2212 single-crystal near-optimum doping. The Cu K-edge XMCD signal was measured at ID12 beamline of ESRF with the k-vector of X-ray beam parallel to c-axis, i.e., with the electric field of X-ray beam E//ab, using a 17-T magnetic field parallel to the c-axis of a Bi2212 single crystal. Numerical simulations of the XMCD signal of Bi2212 by multiple scattering theory have shown agreement with the experimental XMCD signal only for the local structure with noncentrosymmetric Bb2b space group of Bi2Sr2CaCu2O8+y .


Bi2Sr2CaCu2O8+y (Bi2212) X-ray absorption near edge structure (XANES) X-ray magnetic circular dichroism (XMCD) Cu K-edge Noncentrosymmetric superconductivity 



The experiment has been supported by superstripes-onlus. The experiments were performed on beamline ID12 at the European Synchrotron Radiation Facility (ESRF), Grenoble, France. We are grateful to ESRF for beam time allocation and traveling support and ESRF staff for providing assistance in using beamline.

Funding Information

Wei Xu acknowledges the financial support from NSFC (Grant No. U1532128) and LNF from the framework of INFN&IHEP collaboration.


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© Springer Science+Business Media, LLC, part of Springer Nature 2017

Authors and Affiliations

  • Andrey A. Ivanov
    • 1
    Email author return OK on get
  • Valentin G. Ivanov
    • 1
  • Alexey P. Menushenkov
    • 1
  • Fabrice Wilhelm
    • 2
  • Andrei Rogalev
    • 2
  • Alessandro Puri
    • 3
  • Boby Joseph
    • 4
  • Wei Xu
    • 5
  • Augusto Marcelli
    • 6
    • 7
  • Antonio Bianconi
    • 1
    • 7
    • 8
  1. 1.National Research Nuclear University Moscow Engineering Physics Institute (MEPhI)MoscowRussia
  2. 2.European Synchrotron Radiation Facility (ESRF)Grenoble Cedex 9France
  3. 3.CNR-IOM-OGG, c/o ESRF LISA CRGGrenobleFrance
  4. 4.Sincrotrone ElettraBasovizzaItaly
  5. 5.Beijing Synchrotron Radiation Facility, Institute of High Energy PhysicsChinese Academy of SciencesBeijingPeople’s Republic of China
  6. 6.Istituto Nazionale di Fisica Nucleare Laboratori Nazionali di FrascatiFrascatiItaly
  7. 7.Rome International Centre for Material Science Superstripes (RICMASS)RomeItaly
  8. 8.Institute of Crystallography, Consiglio Nazionale delle Ricerche (CNR-IC)MonterotondoItaly

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