E(1g) model of superconducting UPt3

Article

关键词: UPPER CRITICAL-FIELD;    EFFECTIVE MAGNETIC-MOMENTS;    PHASE-DIAGRAM;    HEAVY FERMIONS;    UNCONVENTIONAL SUPERCONDUCTIVITY;    DOUBLE TRANSITION;    ORDER-PARAMETER;    KONDO LATTICES;    WILSON RATIO;    FREE-ENERGY;   

DOI  :  10.1103/PhysRevB.53.12346

来源: SCIE

【 摘 要 】

The phase diagram of superconducting UPt3 is explained in a Ginzburg-Landau theory starting from the hypothesis that the order parameter is a pseudo-spin-singlet which transforms according to the E(1g) representation of the D-6h point group. We show how to compute the positions of the phase boundaries both when the applied held is in the basal plane and when it is along the c axis. The experimental phase diagrams, as determined by longitudinal sound velocity data, can be fit using a single set of parameters. In particular the crossing of the upper critical field curves for the two field directions and the apparent isotropy of the phase diagram are reproduced. The former is a result of the magnetic properties of UPt3 and their contribution to the free energy in the superconducting state. The latter is a consequence of an approximate particle-hole symmetry. Finally, we extend the theory to finite pressure and show that, in contrast to other models, the E(1g) model explains the observed pressure dependence of the phase boundaries.

【 授权许可】

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