Pair wave function symmetry in UTe2 from zero-energy surface state visualization

Journal article

Although nodal spin-triplet topological superconductivity appears probable in uranium ditelluride (UTe₂), its superconductive order parameter Δ_k remains unestablished. In theory, a distinctive identifier would be the existence of a superconductive topological surface band, which could facilitate zero-energy Andreev tunneling to an s-wave superconductor and also distinguish a chiral from a nonchiral Δ_k through enhanced s-wave proximity. In this study, we used s-wave superconductive scan tips and detected intense zero-energy Andreev conductance at the UTe₂ (0-11) termination surface. Imaging revealed subgap quasiparticle scattering interference signatures with a-axis orientation. The observed zero-energy Andreev peak splitting with enhanced s-wave proximity signifies that Δ_k of UTe₂ is a nonchiral state: B_1u, B_2u, or B_3u. However, if the quasiparticle scattering along the a axis is internodal, then a nonchiral B_3u state is the most consistent for UTe₂.

Authors: Gu, Q; Wang, S; Carroll, JP; Zhussupbekov, K; Broyles, C

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Association for the Advancement of Science
• Journal: Science
• Volume: 388
• Issue: 6750
• Pages: 938-944
• Publication date: 2025-05-29
• Acceptance date: 2025-04-02
• DOI: 10.1126/science.adk7219
• EISSN: 1095-9203
• ISSN: 0036-8075
• Language: English