2006/04/07 by Yan Chen, T. M. Rice, Fu‐Chun Zhang +1 · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.97.237004
published as Physical Review Letters 97, 237004 (2006). · 10 pages, 4 figures
arxiv created 2006/04/07 · openalex publication_date 2006/12/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We use an extended t\mathrm\text\ensuremath-J model to study a single hole bound to a Na+ acceptor in Ca_2\ensuremath-xNaxCuO2Cl2. For parameters suitable to cuprates, the ground state has a twofold degeneracy, corresponding to even (odd) reflection symmetry around the x (y) axes. The conductance pattern of the broken symmetry state is anisotropic as the tip of a tunneling microscope scans above the Cu\mathrm\text\ensuremath-O\mathrm\text\ensuremath-Cu bonds along the x (y) axes. This anisotropy is pronounced at lower voltages but reduced at higher voltages. Our theory agrees qualitatively with recent data of scanning tunneling microscopy showing broken local rotational symmetry.