Transport Study of Bismuth Halide Series

The novel one-dimensional van der Waals materials Bi4X4 (X=Bi, I) constitute a promising platform to explore the topological phases. Theoretical calculation has revealed large bulk band gaps, gapless edge states, and higher order topological phases, which have also been experimentally proved. Despite the progress achieved by scanning tunneling microscopy and the angle-resolved photoemission spectroscopy, transport study on this platform remains elusive. Here we demonstrate the preliminary transport features of bismuth halide series with different components and discuss the evidence of edge states in this material.