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Two nonmagnetic impurities in the DSC and DDW state of the cuprate superconductors as a probe for the pseudogap

Brian M. Andersen
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Abstract

The quantum interference between two nonmagnetic impurities is studied numerically in both the d-wave superconducting (DSC) and the d-density wave (DDW) state. In all calculations we include the tunnelling through excited states from the CuO$_2$ planes to the BiO layer probed by the STM tip. Compared to the single impurity case, a systematic study of the modulations in the two-impurity local density of states can distinguish between the DSC or DDW states. This is important if the origin of the pseudogap phase is caused by preformed pairs or DDW order. Furthermore, in the DSC state the study of the LDOS around two nonmagnetic impurities provide further tests for the potential scattering model versus more strongly correlated models.

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Brian M. Andersen. 2003-07-21. Two nonmagnetic impurities in the DSC and DDW state of the cuprate superconductors as a probe for the pseudogap. https://doi.org/10.1103/physrevb.68.094518

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