Sliding-induced topological transitions in bilayer biphenylene

Abstract The complex geometry of biphenylene materials offers alternative routes for exploring novel stacking configurations achieved by piling up carbon-thin sheets. Here we investigate sliding-induced topological transitions in biphenylene bilayers, proposing various novel stacking configurations. They are analyzed from a symmetry perspective and described in detail, highlighting the intricate patterns of type-II Dirac cone crossings. Topological changes in the Fermi surface are assessed via the Euler characteristic, linking each transition to its corresponding symmetry, which can be experimentally tested by conductance measurements. Moreover, the ability to tune these topological properties by sliding the layers provides a simpler and more effective way to observe such phenomena.