Stoner gap in the superconducting ferromagnet UGe2

Abstract

We report the temperature ($T$) dependence of ferromagnetic Bragg peak intensities and dc magnetization of the superconducting ferromagnet UGe2 under pressure ($P$). We have found that the low-$T$ behavior of the uniform magnetization can be explained by a conventional Stoner model. A functional analysis of the data produces the following results: The ferromagnetic state below a critical pressure can be understood as the perfectly polarized state, in which heavy quasiparticles occupy only majority spin bands. A Stoner gap $\Delta (P)$ decreases monotonically with increasing pressure and increases linearly with magnetic field. We show that the present analysis based on the Stoner model is justified by a consistency check, i.e., comparison of density of states at the Fermi energy deduced from the analysis with observed electronic specific heat coeffieients. We also argue the influence of the ferromagnetism on the superconductivity.

arXiv comment5 pages, 4 figures. to be published in Phys. Rev. B

References in corpus (6)

• Pressure dependence of the magnetization in the ferromagnetic superconductor UGe_2
• Magnetism, Spin-Orbit Coupling, and Superconducting Pairing in UGe${}_2$
• Ferromagnetic superconductivity driven by changing Fermi surface topology
• Coupled CDW and SDW Fluctuations as an Origin of Anomalous Properties of Ferromagnetic Superconductor UGe_2
• Magnetic Properties of a Pressure-induced Superconductor UGe${}_2$
• Heat Capacity of the Pressure-induced Superconductivity in Itinerant Ferromagnet UGe${}_2$

Cited by in corpus (4)

• Field Re-entrant Superconductivity Induced by the Enhancement of Effective Mass in URhGe
• Electronic structure of UGe${}_2$ at ambient pressure: comparison with X-ray photoemission spectra
• Optical spectra of the heavy fermion uniaxial ferromagnet UGe${}_2$
• Coexisting Kondo hybridization and itinerant f-electron ferromagnetism in UGe2