Influence of Zn impurities on low-energy excitation spectrum in Bi_2Sr_2CaCu_2O_8+x by angle-resolved photoemission
Abstract
We study spectral change of low-energy quasiparticles upon doping Zn impurities in Bi_2Sr_2Ca(Cu_1-yZn_y)_2O_8+x single crystals using angle-resolved photoemission. By comparing Zn-doped samples (Tc = 83 K) to Zn-free samples (Tc = 91 K), we found that along the nodal direction, the additional non-dispersive state due to Zn impurities are created near the Fermi energy in the superconducting state. However, these localized impurity states are not observed in the normal state. At the anti-nodal point, the spectral weight of the coherent peak is greatly suppressed in the Zn-doped samples, consistent with the observation of the strong reduction of the superfluid density. Theoretical implications will be also discussed.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2002
- Bibcode:
- 2002APS..MARU13002D