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Superconductivity on the threshold of magnetism in CePd2Si2 and CeIn3

F. M. Grosche·I. R. Walker·S. R. Julian·N. D. Mathur·D. M. Freye·M. J. Steiner·G. G. Lonzarich
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Abstract

The magnetic ordering temperature of some rare earth based heavy fermion compounds is strongly pressure-dependent and can be completely suppressed at a critical pressure, p$_c$, making way for novel correlated electron states close to this quantum critical point. We have studied the clean heavy fermion antiferromagnets CePd$_2$Si$_2$ and CeIn$_3$ in a series of resistivity measurements at high pressures up to 3.2 GPa and down to temperatures in the mK region. In both materials, superconductivity appears in a small window of a few tenths of a GPa on either side of p$_c$. We present detailed measurements of the superconducting and magnetic temperature-pressure phase diagram, which indicate that superconductivity in these materials is enhanced, rather than suppressed, by the closeness to magnetic order.

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F. M. Grosche, I. R. Walker, S. R. Julian, N. D. Mathur, D. M. Freye, M. J. Steiner, G. G. Lonzarich. 2000-12-07. Superconductivity on the threshold of magnetism in CePd2Si2 and CeIn3. https://doi.org/10.1088/0953-8984%2F13%2F12%2F309

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