Abstract
In this Letter, we analyze, using scanning tunneling spectroscopy, the density of electronic states in nearly optimally doped in zero magnetic field. Focusing on the superconducting gap, we find patches of what appear to be two different phases in a background of some average gap, one with a relatively small gap and sharp large coherence peaks and one characterized by a large gap with broad weak coherence peaks. We compare these spectra with calculations of the local density of states for a simple phenomenological model in which a patch with an enhanced or suppressed -wave gap amplitude is embedded in a region with a uniform average -wave gap.
- Received 10 August 2005
DOI:https://doi.org/10.1103/PhysRevLett.96.017007
©2006 American Physical Society