Valence fluctuation mediated superconductivity in CeCu2Si2
arXiv:cond-mat/0509787 · doi:10.1016/j.physb.2006.01.123
Abstract
It has been proposed that there are two types of superconductivity in CeCu2Si2, mediated by spin fluctuations at ambient pressure, and by critical valence fluctuations around a charge instability at a pressure P_v \simeq 4.5 GPa. We present in detail some of the unusual features of this novel type of superconducting state, including the coexistence of superconductivity and huge residual resistivity of the order of the Ioffe-Regel limit, large and pressure dependent resistive transition widths in a single crystal measured under hydrostatic conditions, asymmetric pressure dependence of the specific heat jump shape, unrelated to the resistivity width, and negative temperature dependence of the normal state resistivity below 10 K at very high pressure.
4 pages, 4 figures; Proceedings SCES '05
References in corpus (4)
- Signatures of valence fluctuations in CeCu2Si2 under high pressure
- Huge Enhancement of Impurity Scattering due to Critical Valence Fluctuations in a Ce-Based Heavy Electron System
- Strain enhancement of superconductivity in CePd2Si2 under pressure
- Anisotropy, disorder, and superconductivity in CeCu2Si2 under high pressure