Interface-Driven Electronic Structure Modulation in Epitaxial α-Bi Moiré Superlattices on BSCCO

Moiré superlattices have emerged as a frontier in condensed matter physics for their ability to periodically modulate electronic bands and induce novel quantum states. We report the molecular beam epitaxy (MBE) growth of high-quality α-Bi bilayers on Bi₂Sr₂CaCu₂O_8+δ (BSCCO) substrates. The stabilization of this α-phase, distinct from bulk rhombohedral Bi, underscores the dominant role of interface interactions. Scanning tunneling microscopy (STM) imaging reveals atomically resolved Moiré superlattices, whose periodicity is precisely reproduced by structural simulations. Angle-resolved photoemission spectroscopy (ARPES) measurements uncover a clear reconstruction of the electronic states, demonstrating strong modulation of the band structure by the substrate potential. These results establish epitaxial α-Bi/BSCCO as a promising platform for engineering interface-driven quantum materials.