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arXiv · 0904.3138

Studies of superconductivity and structure for CaC6 to pressures above 15 GPa

M. Debessai·J. J. Hamlin·J. S. Schilling·Y. Meng·D. Rosenmann·D. G. Hinks·H. Claus
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Abstract

The dependence of the superconducting transition temperature Tc of CaC6 has been determined as a function of hydrostatic pressure in both helium-loaded gas and diamond-anvil cells to 0.6 and 32 GPa, respectively. Following an initial increase at the rate +0.39(1) K/GPa, Tc drops abruptly from 15 K to 4 K at 10 GPa. Synchrotron x-ray measurements to 15 GPa point to a structural transition near 10 GPa from a rhombohedral to a higher symmetry phase.

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M. Debessai, J. J. Hamlin, J. S. Schilling, Y. Meng, D. Rosenmann, D. G. Hinks, H. Claus. 2009-04-20. Studies of superconductivity and structure for CaC6 to pressures above 15 GPa. https://doi.org/10.1103/physrevb.82.132502

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