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arXiv · 0906.1265

Experimental evidence of chemical-pressure-controlled superconductivity in cuprates

S. Sanna·S. Agrestini·K. Zheng·R. De Renzi·N. L. Saini
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Abstract

X-ray absorption spectroscopy (XAS) and high resolution X-ray diffraction are combined to study the interplay between electronic and lattice structures in controlling the superconductivity in cuprates with a model charge-compensated CaxLa1-xBa1.75-xLa0.25+xCu3Oy (0<x<0.5, y=7.13) system. In spite of a large change in Tc, the doped holes, determined by the Cu L and O K XAS, hardly show any variation with the x. On the other hand, the CuO2 plaquette size shows a systematic change due to different size of substituted cations. The results provide a direct evidence for the chemical pressure being a key parameter for controlling the superconducting ground state of the cuprates.

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S. Sanna, S. Agrestini, K. Zheng, R. De Renzi, N. L. Saini. 2009-06-08. Experimental evidence of chemical-pressure-controlled superconductivity in cuprates. https://doi.org/10.1209/0295-5075/86/67007

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