THE SPECTATOR FERMION SUPERFLUID MODEL FOR HIGH-TC AND HEAVY FERMION SUPERCONDUCTORS - THE PRESSURE EFFECT

We show that the pressure dependence of T(c) for the high-T(c) and heavy fermion superconductors can be explained within a generalized electron-hole liquid model called the spectator fermion superfluid model. We assign the structure (e-, B++) for the hole-doped and (e-, B--) for the electron-doped superconductors. This classification explains in a natural way the observed pressure asymmetry. In both cases, the experimental pressure gradients of T(c) are fitted well if the spectator component has a much smaller effective mass than the bosons. The pressure gradient of T(c) is predicted to be smallest near the maximum T(c) point, in agreement with experiments. The theory predicts an increase of the specific heat linear term with pressure for all four spectator categories. The pressure dependences of T(c) and c(p)(T(c)) for the HFS-compounds UBe13 and UPt3 are brought into agreement with experiment if we assign the structure (h+, B++) to them. We show that the pressure dependences of the Hall coefficient and the Hall resistance agree with experiments for HTS-compounds for T > T(c).