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arXiv · 0908.0412

On the Origin of the Checkerboard Pattern in Scanning Tunneling Microscopy Maps of Underdoped Cuprate Superconductors

Kai-Yu Yang·Wei-Qiang Chen·T. M. Rice·Fu-Chun Zhang
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Abstract

The checkerboard pattern in the differential conductance maps on underdoped cuprates appears when the STM is placed above the O-sites in the outermost CuO$_{\text{2}}$-plane. In this position the interference between tunneling paths through the apical ions above the neighboring Cu-sites leads to an asymmetric weighting of final states in the two antinodal regions of ${\boldsymbol{k}}$-space. The form of the asymmetry in the differential conductance spectra in the checkerboard pattern favors asymmetry in the localization length rather than a nematic displacement as the underlying origin.

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Kai-Yu Yang, Wei-Qiang Chen, T. M. Rice, Fu-Chun Zhang. 2009-08-04. On the Origin of the Checkerboard Pattern in Scanning Tunneling Microscopy Maps of Underdoped Cuprate Superconductors. https://doi.org/10.1103/physrevb.80.174505

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