Abstract
We show that a multilayer analysis of the infrared -axis response of provides important new information about the anomalous normal-state properties of underdoped cuprate high temperature superconductors. In addition to competing correlations which give rise to a pseudogap that depletes the low-energy electronic states below , it enables us to identify the onset of a precursor superconducting state below . We map out the doping phase diagram of which reaches a maximum of 180 K at strong underdoping and present magnetic field dependent data which confirm our conclusions.
- Received 15 September 2010
DOI:https://doi.org/10.1103/PhysRevLett.106.047006
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