ISSN:
1573-7357
Keywords:
74.62.Fj
;
74.70.Wz
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract In BaxC60 superconductivity (sc) at Tc=(6.8±0.2) K is associated with the x=4 phase. Here we present pressure studies of Tc of a BaxC60 sample (dTc/dp= −1.9 K/GPa) which exhibits a large volume fraction of the x=4 phase. In the alkali-fullerides K60C60 and Rb3C60 Tc is governed by the electronic density of states N(EF) (Tc ∝exp{−1/N(EF)V}). The dependence of N(EF) on volume can be approximated by N(EF)=N0 d eff 3, where deff is the surface to surface distance of neighboured C60-molecules. This relationship is corroborated by (TC,d)-data of various compounds of the form A3−xBxC60 (A: K, Rb; B: K, Rb, Cs; x≤2). Strong deviation from this behavior is found for the alkaline-fulleride superconductor Ba4C60. This deviation is attributed to the hybridization of alkaline-metal s-, d-states and C60 π-states.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00753944
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