Pairing symmetries of multiple superconducting phases in UTe2: Competition between ferromagnetic and antiferromagnetic fluctuations

Abstract

The putative spin-triplet superconductor UTe2 exhibits multiple superconducting phases under applied pressure [D. Braithwaite et al., Commun. Phys. 2, 147 (2019)]. The clarification of pairing mechanisms and symmetries of gap functions are essentially important for understanding the multiple-phase diagram. Since the coexistence of ferromagnetic and antiferromagnetic spin fluctuations with Ising-like anisotropy is suggested from measurements of magnetic susceptibilities and neutron scattering measurements, it is expected that the interplay between these spin fluctuations plays a crucial role in the emergence of the multiple superconducting phases. Motivated by these observations, we examine the spin-fluctuation-mediated pairing mechanism, analyzing the linearized Eliashberg equations for an effective model of f-electron bands. It is found that the Ising-like ferromagnetic fluctuations stabilize spin-triplet pairings in either the Au or B3u states, whereas Ising-like antiferromagnetic fluctuations stabilize spin-triplet pairings in the B1u state. These results provide a plausible scenario elucidating the multiple superconducting phases under pressure.

8 pages, 7 figures

References in corpus (22)

• Unconventional Superconductivity in Heavy Fermion UTe2
• Unconventional Superconductivity in UTe2
• Multiple Superconducting Phases and Unusual Enhancement of the Upper Critical Field in UTe2
• Single-component superconducting state in UTe2 at 2 K
• Incommensurate Spin Fluctuations in the Spin-triplet Superconductor Candidate UTe${}_2$
• Periodic Anderson model for magnetism and superconductivity in UTe2
• First Observation of de Haas-van Alphen Effect and Fermi Surfaces in Unconventional Superconductor UTe2
• Topological band and superconductivity in UTe${}_2$
• Low-dimensional antiferromagnetic fluctuations in the heavy-fermion paramagnetic ladder UTe${}_2$
• Large Reduction in the $a$-axis Knight Shift on UTe${}_2$ with $T_{\mathrm{c}}$ = 2.1 K
• Field-induced tuning of the pairing state in a superconductor
• Chiral superconductivity in UTe2 probed by anisotropic low-energy excitations
• Quasi-2D Fermi surface in the anomalous superconductor UTe2
• The fate of time-reversal symmetry breaking in UTe2
• Fully gapped pairing state in spin-triplet superconductor UTe${}_2$
• Magnetic Properties under Pressure in Novel Spin-Triplet Superconductor UTe2
• Field-Induced Superconductivity near the Superconducting Critical Pressure in UTe2
• Triplet pairing mechanisms from Hund's-Kondo models: applications to UTe${}_2$ and CeRh${}_2$As${}_2$
• Superconducting-Spin Reorientation in Spin-Triplet Multiple Superconducting Phases of UTe2
• Feedback of superconductivity on the magnetic excitation spectrum of UTe${}_2$
• Magnetic reshuffling and feedback on superconductivity in UTe2 under pressure
• Possible Realization of Topological Crystalline Superconductivity with Time-Reversal Symmetry in UTe2

Cited by in corpus (13)

• Superconducting Diode Effect in Multiphase Superconductors
• Unconventional $s$-Wave Pairing with Point-Node-Like Gap Structure in UTe${}_2$
• Anisotropic paramagnetic response of topological Majorana surface states in the superconductor ${\text{UTe}}_2$
• Nodal superconducting gap structure and topological surface states of UTe${}_2$
• Spin caloritronics as a probe of nonunitary superconductors
• Self-reconstruction of order parameter in spin-triplet superconductor UTe${}_2$
• Majorana multipole response with magnetic point group symmetry
• Reciprocal and nonreciprocal paraconductivity in bilayer multiphase superconductors
• Two-dimensional flat band on the (011) surface of UTe${}_2$: Implication for STM measurements with a superconducting tip
• Higher-order topological phases for time-reversal-symmetry breaking superconductivity in UTe${}_2$
• Metamagnetism in the high-pressure tetragonal phase of UTe${}_2$
• Magnetic fluctuations and anisotropy in UTe2: a multi-orbital study based on GGA+U and RPA
• Electronic structure of UTe${}_2$ under pressure