Topological electronic properties of Bismuth Selenide nanoribbon slab with zigzag edge

A 3D topological insulator based on Bismuth Selenide (Bi<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>Se<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>) slab has been investigated. In this study, using density functional theory (DFT) and a Wannier-based tightbinding model, we computed various electronic properties, including the band structure and local density of states (LDOS) for both bulk Bi<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>Se<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> slab and its zigzag-edged nanoribbon counterpart. The band structure reveals that Bi<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>Se<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> slabs exhibit surface states with a Dirac cone at the Gamma point. From the LDOS analysis, we find that allowed density of states are confined to the surfaces of the zigzag nanoribbon slab. This study provides valuable insights for designing future device applications.