Imaging the granular structure of high-Tc superconductivity in underdoped Bi2Sr2CaCu2O8+x
Preprint
- 12 December 2001
Abstract
Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions through which they communicate by Josephson tunneling to establish the macroscopic superconducting state [1]. Although crystals of the cuprate high-Tc superconductors are not granular in a structural sense, theory indicates that at low hole densities the holes can become concentrated at some locations resulting in hole-rich superconducting domains [2-5]. Granular superconductivity due to Josephson tunneling through 'undoped' regions between such domains would represent a new paradigm for the underdoped cuprates. Here we report studies of the spatial interrelationships between STM tunneling spectra in underdoped Bi2Sr2CaCu2O8+x. They reveal an apparent spatial segregation of the electronic structure into ~3nm diameter domains (with superconducting characteristics and local energy gap delta50(2.5) meV. These observations suggest that underdoped Bi2Sr2CaCu2O8+x is a mixture of two different short-range electronic orders with the long-range characteristics of a granular superconductor.Keywords
All Related Versions
- Version 1, 2001-12-12, ArXiv
- Published version: Nature, 415 (6870), 412.
This publication has 0 references indexed in Scilit: