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arXiv · 0903.1808

Pressure-Induced Superconductivity in Europium Metal

M. Debessai·T. Matsuoka·J. J. Hamlin·J. S. Schilling·K. Shimizu
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Abstract

Divalent Eu (4f7, J=7/2) possesses a strong local magnetic moment which suppresses superconductivity. Under sufficient pressure it is anticipated that Eu will become trivalent (4f6, J=0) and a weak Van Vleck paramagnet, thus opening the door for a possible superconducting state, in analogy with Am metal (5f6, J=0) which superconducts at 0.79 K. We present ac susceptibility and electrical resistivity measurements on Eu metal for temperatures 1.5 - 297 K to pressures as high as 142 GPa. At approximately 80 GPa Eu becomes superconducting at Tc = 1.8 K; Tc increases linearly with pressure to 2.75 K at 142 GPa. Eu metal thus becomes the 53rd known elemental superconductor in the periodic table.

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M. Debessai, T. Matsuoka, J. J. Hamlin, J. S. Schilling, K. Shimizu. 2009-03-10. Pressure-Induced Superconductivity in Europium Metal. https://doi.org/10.1088/1742-6596/215/1/012034

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