Impurity in a d-wave superconductor: Kondo effect and STM spectra.
نویسندگان
چکیده
We present a theory for recent STM studies of Zn impurities in the superconductor Bi2Sr2CaCu2O8+delta, 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.
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عنوان ژورنال:
- Physical review letters
دوره 86 2 شماره
صفحات -
تاریخ انتشار 2001