Superconductivity in the Presence of Strong Pauli Paramagnetism: CeCu2Si2<

Abstract

after annealing to 20 K, lnR-T ' ' was found. These films did not exhibit superconductivity as measured resistively down to the lowest temperatures attainable (T-1.5 K). The above-described behavior suggests that the Hg-Xe system exhibits a metal-nonmetal transition which occurs with a dependence on concentration and with a critical concentration close to that of continuous percolation in 3D. Beyond the percolation threshold, the systems acquire a negative TCR but are still superconductors. With further increase in Xe concentration, a regime in which the conductivity is dominated by hopping is entered. The approach to an insulating configuration beyond the percolation threshold is probably the Mott-Anderson transition of Refs. 2-4 and is accompanied by the eventual disappearance of superconductivity as determined resistively. The authors would like to thank R. Mikkelson for many helpful discussions. This work was supported by the U. S. Department of Energy under Contract No. EY-V6-S-02-1569-A002.

Heavy fermion superconductor CeCu2Si2under high pressure: Multiprobing the valence crossover

“…Even though investigations started already in 1979, 1 CeCu 2 Si 2 still carries key enigmas of heavy fermion (HF) superconductivity (SC). Numerous (pressure) studies on other Ce-based HF compounds, notably concerning the 115 family, focus on the magnetic instability or magnetic quantum critical point as a driving force for exotic behaviors such as unconventional SC.…”

Magnetism and Negative Magnetoresistance of Two Magnetically Ordering, Rare-Earth-Containing Zintl phases with a New Structure Type: EuGa2Pn2 (Pn = P, As)

“…Many of these interesting properties are found in materials of composition AM 2 X 2 (M = transition or main group element, X=Group 13-15 element), which is a particularly diverse structural class. 8,14,[18][19][20][21][22] Recent discovery of colossal magnetoresistance (CMR) in several of the magnetically ordering AM 2 X 2 compounds (e.g., EuIn 2 P 2 and EuIn 2 As 2 ), 8,14 provides incentive for additional research into these types of compounds in order to provide correlations between material composition, structure, and the observed electrical, magnetic, and/or magneto-electronic properties.…”

Study on Unconventional Superconductivity after the BCS Paradigm

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