The highest temperature superconductors are electronically inhomogeneous at the nanoscale, suggesting the existence of a local variable which could be harnessed to enhance the superconducting pairing. Here we report the relationship between local doping and local strain in the cuprate superconductor Bi2Sr2CaCu2O8+x. We use scanning tunneling microscopy to discover that the crucial oxygen dopants are periodically distributed, in correlation with local strain. Our picoscale investigation of the intra-unit-cell positions of all oxygen dopants provides essential structural input for a complete microscopic theory.
@article{arxiv.1412.6088,
title = {Nanoscale interplay of strain and doping in a high-temperature superconductor},
author = {Ilija Zeljkovic and Jouko Nieminen and Dennis Huang and Tay-Rong Chang and Yang He and Horng-Tay Jeng and Zhijun Xu and Jinsheng Wen and Genda Gu and Hsin Lin and Robert S. Markiewicz and Arun Bansil and Jennifer E. Hoffman},
journal= {arXiv preprint arXiv:1412.6088},
year = {2014}
}