Holonomic quantum computation on graphene from Atiyah-Singer index theorem

Abstract

We investigate the emergence of geometric phases in graphene-based nanostructures through the lens of the Atiyah-Singer index theorem. By modeling low-energy quasiparticles in curved graphene geometries as Dirac fermions, we demonstrate that topological defects arising from the insertion of pentagonal or heptagonal carbon rings generate effective gauge fields that induce quantized Berry phases. We derive a compact expression for the geometric phase in terms of the genus and number of open boundaries of the structure, providing a topological classification of zero-energy modes. This framework enables a deeper understanding of quantum holonomies in graphene and their potential application in holonomic quantum computation. Our approach bridges discrete lattice models with continuum index theory, yielding insights that are both physically intuitive and experimentally accessible.