Impurity-induced low-energy resonances in Bi2Sr2CaCu2O8+delta

Article

关键词: LOCAL ELECTRONIC-STRUCTURE;    T-C SUPERCONDUCTOR;    STM SPECTRA;    DEFECTS;    STATES;    ATOMS;   

DOI  :  10.1103/PhysRevB.70.140510

来源: SCIE

【 摘 要 】

We study sharp low-energy resonance peaks in the local density of states (LDOS) induced by Zn impurities or possible Cu vacancies in superconducting Bi2Sr2CaCu2O8+delta. The measured structure of these near-zero-bias resonances is quantitatively reproduced by an extended impurity potential without invoking internal impurity states or sophisticated tunneling models. The Zn potential extends at least to the nearest-neighbor Cu sites, and the range of order parameter suppression extends at least 8 Angstrom away from the Zn site. We further show that the local spin susceptibilities near Zn impurities increase rather than decrease with decreasing temperature in the superconducting state due to the sharp increase of the LDOS near the Fermi level.

【 授权许可】

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