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Oxygen isotope effect on the superconductivity and stripe phase in La$_{1.6-x}$Nd$_{0.4}$Sr$_{x}$CuO$_4$

G. Y. Wang·J. D. Zhang·R. L. Yang·X. H. Chen
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Abstract

The oxygen isotope effect on the superconductivity, stripe phase and structure transition is systematically investigated in La$_{1.6-x}$Nd$_{0.4}$Sr$_{x}$CuO$_4$ with static stripe phase. Substitution of $^{16}$O by $^{18}$O leads to a decrease in superconducting transition temperature T$_C$, while enhances the temperature of the structural transition from low-temperature-orthorhombic (LTO) phase to low-temperature-tetragonal (LTT) phase. Compared to the Nd free sample, a larger isotope effect on $T_C$ is observed in La$_{1.6-x}$Nd$_{0.4}$Sr$_{x}$CuO$_4$. These results indicate that the distortion of CuO$_2$ plane suppresses the superconductivity, giving a direct evidence for the competing of stripe phase and superconductivity because the distortion of CuO$_2$ plane enhances the stripe phase.

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G. Y. Wang, J. D. Zhang, R. L. Yang, X. H. Chen. 2007-03-25. Oxygen isotope effect on the superconductivity and stripe phase in La$_{1.6-x}$Nd$_{0.4}$Sr$_{x}$CuO$_4$. https://doi.org/10.1103/physrevb.75.212503

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