Abstract
The search for unconventional superconductivity in Weyl semimetal materials is currently an exciting pursuit, since such superconducting phases could potentially be topologically non-trivial and host exotic Majorana modes. The layered material TaIrTe4 is a newly predicted time-reversal invariant type II Weyl semimetal with the minimum number of Weyl points. Here, we report the discovery of surface superconductivity in Weyl semimetal TaIrTe4. Our scanning tunneling microscopy/spectroscopy (STM/STS) visualizes Fermi arc surface states of TaIrTe4 that are consistent with the previous angle-resolved photoemission spectroscopy results. By a systematic study based on STS at ultralow temperature, we observe uniform superconducting gaps on the sample surface. The superconductivity is further confirmed by electrical transport measurements at ultralow temperature, with an onset transition temperature (Tc) up to 1.54 K being observed. The normalized upper critical field h*(T/Tc) behavior and the stability of the superconductivity against the ferromagnet indicate that the discovered superconductivity is unconventional with the p-wave pairing. The systematic STS, and thickness- and angular-dependent transport measurements reveal that the detected superconductivity is quasi-1D and occurs in the surface states. The discovery of the surface superconductivity in TaIrTe4 provides a new novel platform to explore topological superconductivity and Majorana modes.
Highlights
Weyl semimetals, which possess nodal points in the bulk and Fermi arc states in the surface, have generated considerable research interest in the recent years [1,2,3,4,5,6,7,8,9,10,11,12]
The uniform superconducting gap on the sample surface, residual resistance below Tc, nearly thickness-independent ultralow critical current, and anisotropic upper critical field behavior indicate that the superconductivity occurs in the surface states
Our results suggest that TaIrTe4 is a new promising candidate of topological superconductors
Summary
Weyl semimetals, which possess nodal points in the bulk and Fermi arc states in the surface, have generated considerable research interest in the recent years [1,2,3,4,5,6,7,8,9,10,11,12]. The theoretical studies have shown that the presence of superconductivity in Weyl semimetal may lead to a bunch of novel topological phases, including the time-reversal invariant topological superconductor [17], Fulde-Ferrell-Larkin-Ovchinnikov superconductors [18,19,20], and chiral non-Abelian Majorana fermions protected by second Chern numbers [21]. These predictions suggest that turning a Weyl semimetal into superconducting state may provide a promising way to explore topological superconductivity and Majorana modes, which can be applied to topological quantum computation [22,23,24]. To observe superconductivity in simpler Weyl semimetals possessing minimal number of Weyl points is highly desired
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
