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Magic Doping Fractions in High-Temperature Superconductors

Seiki Komiya·Han-Dong Chen·Shou-Cheng Zhang·Yoichi Ando
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Abstract

We report hole-doping dependence of the in-plane resistivity ρ_{ab} in a cuprate superconductor La_{2-x}Sr_{x}CuO_{4}, carefully examined using a series of high-quality single crystals. Our detailed measurements find a tendency towards charge ordering at particular rational hole doping fractions of 1/16, 3/32, 1/8, and 3/16. This observation appears to suggest a specific form of charge order and is most consistent with the recent theoretical prediction of the checkerboard-type ordering of the Cooper pairs at rational doping fractions x = (2m+1)/2^n, with integers m and n.

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Seiki Komiya, Han-Dong Chen, Shou-Cheng Zhang, Yoichi Ando. 2004-12-27. Magic Doping Fractions in High-Temperature Superconductors. https://doi.org/10.1103/physrevlett.94.207004

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