  Non-trivial Berry phase of graphene leads to unusual quantum correction to
the conductivity. Berry phase of pi in single layer graphene (SLG) and 2pi in
bi-layer graphene (BLG) is expected to reveal weak anti-localization (WAL) and
weak localization (WL), respectively. However, experimentally both WAL and WL
have been observed in graphene devices depending on the strength of different
scattering mechanisms. Graphene superlattice having multiple Dirac cones is
expected to exhibit pi to 2pi Berry phase transition from primary Dirac cone
(PDC) to cloned Dirac cone (CDC). However, its effect on localization physics
has not been explored yet. In this letter we present the magneto-conductance
study in a hexagonal Boron-nitride (hBN)-graphene moire superlattice. Our
results reveal a transition from WAL at PDC to WL at CDC in a single device by
tuning the Fermi energy. The transition is supported by the quantum oscillation
measurements showing a shift of pi phase from PDC to CDC and corresponding
theoretical calculation capturing the Berry phase transition. Thus, our studies
on localization physics in graphene superlattice pave the way to understand the
carrier dynamics at multiple Dirac cones.
