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Experimental proof of a structural origin for the shadow Fermi surface in Bi$_2$Sr$_2$CaCu$_2$O$_{8+delta}$

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 نشر من قبل Mark Golden
 تاريخ النشر 2005
  مجال البحث فيزياء
والبحث باللغة English
 تأليف A. Mans




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By combining surprising new results from a full polarization analysis of nodal angle-resolved photoemission data from pristine and modulation-free Bi$_2$Sr$_2$CaCu$_2$O$_{8+delta}$ with structural information from LEED and {it ab initio} one-step photoemission simulations, we prove that the shadow Fermi surface in these systems has structural origin, being due to orthorhombic distortions from tetragonal symmetry present in both surface and bulk. Consequently, one of the longest standing open issues in the fermiology of these widely studied systems finally meets its resolution.



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