Spin-triplet paired phases inside a ferromagnet induced by Hund's rule coupling and electronic correlations: Application to UGe2

Article

关键词: PRESSURE-INDUCED SUPERCONDUCTIVITY;    COEXISTENCE;    GUTZWILLER;    MAGNETISM;    PHYSICS;   

DOI  :  10.1103/PhysRevB.97.224519

来源: SCIE

【 摘 要 】

We discuss a mechanism of real-space spin-triplet pairing, which is an alternative to the one due to quantum paramagnon excitations, and demonstrate its applicability to UGe2. Both the Hund's rule ferromagnetic exchange and interelectronic correlations contribute to the same extent to the equal-spin pairing, particularly in the regime where the weak-coupling solution does not provide any. The theoretical results, obtained within the orbitally degenerate Anderson lattice model, excellently match the observed phase diagram for UGe2 with the coexistent ferromagnetic (FM1) and superconducting (A(1)-type) phases. Additionally, weak A(2) - and A-type paired phases appear in very narrow regions near the metamaganetic (FM2 -> FM1) and FM1 to paramagnetic first-order phase-transition borders, respectively. The values of magnetic moments in the FM2 and FM1 states are also reproduced correctly in a semiquantitative manner. The Hund's metal regime is also singled out as appearing near the FM1-FM2 boundary.

【 授权许可】

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