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arXiv · 1412.6088

Nanoscale interplay of strain and doping in a high-temperature superconductor

Ilija Zeljkovic·Jouko Nieminen·Dennis Huang·Tay-Rong Chang·Yang He·Horng-Tay Jeng·Zhijun Xu·Jinsheng Wen·Genda Gu·Hsin Lin·Robert S. Markiewicz·Arun Bansil·Jennifer E. Hoffman
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Abstract

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 Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$. 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.

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Ilija Zeljkovic, Jouko Nieminen, Dennis Huang, Tay-Rong Chang, Yang He, Horng-Tay Jeng, Zhijun Xu, Jinsheng Wen, Genda Gu, Hsin Lin, Robert S. Markiewicz, Arun Bansil, Jennifer E. Hoffman. 2014-12-18. Nanoscale interplay of strain and doping in a high-temperature superconductor. https://doi.org/10.1021/nl501890k

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