Pressure-induced change of the pairing symmetry in superconducting CeCu2Si2

Abstract

Low-temperature (T) heat-capacity measurements under hydrostatic pressure of up to p=2.1 GPa have been performed on single-crystalline CeCu2Si2. A broad superconducting (SC) region exists in the T-p phase diagram. In the low-pressure region antiferromagnetic spin fluctuations and in the high-pressure region valence fluctuations had previously been proposed to mediate Cooper pairing. We could identify these two distinct SC regions. We found different thermodynamic properties of the SC phase in both regions, supporting the proposal that different mechanisms might be implied in the formation of superconductivity.

arXiv comment4 pages, 5 figures

References in corpus (4)

• Signatures of valence fluctuations in CeCu2Si2 under high pressure
• Enhanced Valence Fluctuations Caused by f-c Coulomb Interaction in Ce-Based Heavy Electrons: Possible Origin of Pressure-Induced Enhancement of Superconducting Transition Temperature in \Ge and Related Compounds
• Non-Fermi liquid states in the pressurized $CeC{u}_2(S{i}_{1-x}G{e}_x{)}_2$ system: two critical points
• Density Fluctuation Mediated Superconductivity

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