Moire-Assisted Realization of Octahedral MoTe₂ Monolayer

A current key challenge in 2D materials is the realization of emergent quantum phenomena in hetero structures via controlling the moire potential created by the periodicity mismatch between adjacent layers, as highlighted by the discovery of superconductivity in twisted bilayer graphene. Generally, the lattice structure of the original host material remains unchanged even after the moire superlattice is formed. However, much less attention is paid for the possibility that the moire potential can also modify the original crystal structure itself. Here, it is demonstrated that octahedral MoTe2 which is unstable in bulk is stabilized in a commensurate MoTe2/graphene hetero-bilayer due to the moire potential created between the two layers. It is found that the reconstruction of electronic states via the moire potential is responsible for this stabilization, as evidenced by the energy-gap opening at the Fermi level observed by angle-resolved photoemission and scanning tunneling spectroscopies. The present results provide a fresh approach to realize novel 2D quantum phases by utilizing the moire potential.