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arXiv · 1311.5892

Can deeply underdoped superconducting cuprates be topological superconductors?

Yuan-Ming Lu·Tao Xiang·Dung-Hai Lee
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Abstract

The nodal $d_{x^2-y^2}$ superconducting gap is a hallmark of the cuprate high T$_c$ superconductors. Surprisingly recent angle-resolved photoemission spectroscopy of deeply underdoped cuprates revealed a nodeless energy gap which is adhered to the Fermi surface. Importantly this phenomenon is observed for compounds across several different cuprate families. In this letter we propose an exciting possibility, namely the fully gapped state is a topological superconductor.

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Yuan-Ming Lu, Tao Xiang, Dung-Hai Lee. 2013-11-22. Can deeply underdoped superconducting cuprates be topological superconductors?. https://doi.org/10.1038/nphys3021

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