Multiorbital spin-triplet pairing and spin resonance in the heavy-fermion superconductor UTe2

ORAL

Abstract

UTe2 is a candidate spin-triplet superconductor. Among the outstanding issues is the nature of the pairing state. A recent surprising discovery is a resonance in the spin excitation spectrum at an antiferromagnetic (AF) wavevector [1], which stands in apparent contrast to the expected ferromagnetic nature. Here [2], we advanced a theoretical resolution to these seemingly contradictory issues by considering a multiorbital spin-triplet pairing constructed from the dimer of U ions in the unit cell. Because it does not commute with the kinetic part of the Hamiltonian, the pairing function contains both intra- and inter- band terms in the band basis. We demonstrate the existence of a spin resonance at the AF wavevector. Our work illustrates how orbital degrees of freedom can enrich the nature and properties of spin-triplet superconductivity in general.



[1] C. Duan et al., Nature 600, 636 (2021).



[2] L. Chen, H. Hu. C. Lane, E. M. Nica, J.-X. Zhu and Q. Si, "Multiorbital spin-triplet pairing and spin resonance in the heavy-fermion superconductor UTe2”, arXiv:2112.14750.



*Work supported by the DOE BES Award # DE-SC0018197, LANL LDRD, UC Laboratory Fees Research Program, Quantum Science Center, a U.S. DOE Office of Science National QIS Research Center, & CINT, a DOE BES user facility.

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Publication: L. Chen, H. Hu. C. Lane, E. M. Nica, J.-X. Zhu and Q. Si, "Multiorbital spin-triplet pairing and spin resonance in the heavy-fermion superconductor UTe2", arXiv:2112.14750.

Presenters

  • Lei Chen

    • Rice University

Authors

  • Lei Chen

    • Rice University

  • Haoyu Hu

    • Donostia International Physics Center

  • Christopher A Lane

    • Los Alamos National Laboratory

  • Emilian M Nica

    • Arizona State University
    • Rice University

  • Qimiao Si

    • Rice University