Absence of the 1/8 -anomaly in oxygen isotope effect on YBa$_{2}$Cu$_{3}$O$_{y}$

K. Kamiya; T. Masui; S. Tajima; H. Bando; Y. Aiura

doi:10.1103/physrevb.89.060505

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arXiv · 1402.1942

Absence of the 1/8 -anomaly in oxygen isotope effect on YBa$_{2}$Cu$_{3}$O$_{y}$

K. Kamiya·T. Masui·S. Tajima·H. Bando·Y. Aiura

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Abstract

We have prepared oxygen isotope exchanged crystals of impurity-free YBCO with various oxygen concentents, and examined pure doping ($p$) dependance of isotope effect on superconducting transition temperature. With decreasing oxygen contents, the isotope exponent $\alpha$ monotonously increases without any anomaly around $p = 1/8$. The monotonous increase in $\alpha$ indicates that phonons are involved in the mechanism which causes the monotonous $T_c$ suppression with underdoping.

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K. Kamiya, T. Masui, S. Tajima, H. Bando, Y. Aiura. 2014-02-09. Absence of the 1/8 -anomaly in oxygen isotope effect on YBa$_{2}$Cu$_{3}$O$_{y}$. https://doi.org/10.1103/physrevb.89.060505

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