We present a theory for recent STM studies of Zn impurities in the superconductor Bi2Sr2CaCu2O8+δ, using insights from NMR experiments which show that there is a net S = 1/2 moment on the Cu ions near the Zn. We argue that the Kondo spin dynamics of this moment is the origin of the low bias peak in the differential conductance, rather than a resonance in a purely potential scattering model. The spatial and energy dependence of the STM spectra of our model can also fit the experiments.
Physical Review Letters
- Pub Date:
- January 2001
- Condensed Matter - Strongly Correlated Electrons;
- Condensed Matter - Superconductivity
- 4 pages, 2 color figures. Found improved saddle-point with d-wave correlations near the impurity