Scanning Tunneling Microscopy and Spectroscopy of UTe<sub>2</sub>

ORAL

Abstract

Recent findings strongly indicate that UTe2 behaves as a heavy-fermion superconductor displaying traits of a spin-triplet p-wave superconductor, positioning it as an excellent candidate for investigating topological superconductivity. A scanning tunnelling microscopy study previously revealed unusual charge density wave (CDW) and pair density wave (PDW) formations in UTe21-2. In our research, we employed both normal tungsten (W) and superconducting niobium (Nb) tips to expand our understanding of topological superconductors such as UTe2 through scanning tunneling microscopy and spectroscopy (STM/S). We found that UTe2 can be cleaved along different orientation planes, including (0-11) and (001), as well as by U and Te surface terminations, employing STM/S techniques. When using the superconducting Nb tip, we observed a robust zero-bias peak on the (0-11) crystal termination of UTe2 in conductance measurements. Furthermore, our study revealed that the atomic step edge of UTe2 enhances the zero-bias conductance peak (ZBCP), while the U-terminated terrace lacks a ZBCP entirely.

1. Aishwarya, A. et al. Magnetic-field-sensitive charge density waves in the superconductor UTe2. Nature 618, 928–933 (2023).

2. Gu, Q. et al. Detection of a pair density wave state in UTe2. Nature 618, 921–927 (2023).

*We acknowledge support from the Moore Foundation's EPiQS Initiative through Grant GBMF9457 and support from Science Foundation Ireland under Award SFI 17/RP/5445.

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Presenters

  • Kuanysh Zhussupbekov

    • Cornell University

Authors

  • Kuanysh Zhussupbekov

    • Cornell University

  • Qiangqiang Gu

    • Cornell University

  • Shuqiu Wang

    • University of Bristol
    • University of Bristol, University of Oxford, Cornell University

  • Joseph Carroll

    • University College Cork

  • Sheng Ran

    • Washington University in St. Louis

  • Nicholas P Butch

    • National Institute of Standards and Tech

  • Johnpierre Paglione

    • University of Maryland, College Park
    • Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, Maryland 20742, USA

  • Xiaolong Liu

    • University of Notre Dame
    • Notre Dame University

  • Dung-Hai Lee

    • University of California
    • University of California, Berkeley

  • Seamus S Davis

    • University of Oxford
    • University of Oxford, Cornell University, University College Cork
    • Univeristy of Oxford