Observation of Topological Electronic Structure in Quasi-1D Superconductor TaSe3

Topological superconductors (TSCs), with the capability to host Majorana bound states that can lead to non-Abelian statistics and application in quantum computation, have been one of the most intensively studied topics in condensed matter physics recently. To date, only a few compounds have been proposed as candidates of intrinsic TSCs, such as doped topological insulator Cu x Bi 2 Se 3 and iron-based superconductor FeTe 0.55 Se 0.45 . Here, by carrying out synchrotron- and laser-based angle-resolved photoemission spectroscopy, we systematically investigated the electronic structure of a quasi-one-dimensional superconductor TaSe 3 and identified the non-trivial topological surface states. In addition, our scanning tunneling microscopy study revealed a clean cleaved surface with a persistent superconducting gap, proving it suitable for further investigation of potential Majorana modes. These results prove TaSe 3 as a stoichiometric TSC candidate that is stable and exfoliable and therefore a promising platform for the study of rich novel phenomena and application potentials.