2025/12/24 by Affan Safeer, Oktay Güleryüz, Safeer, Affan +9
Materials Science · #2D Materials and Applications #Electronic and Structural Properties of Oxides #Chemical and Physical Properties of Materials
paper · doi:10.48550/arxiv.2512.21163
Single-layer transition metal dihalides grown on conducting substrates were shown to host stable polarons. Here, we investigate polarons in insulating single-layer MnBr2 grown by molecular beam epitaxy on three different substrates, namely graphene on Ir(110), graphene on Ir(111), and Au(111). The number densities and species of polarons observed vary strongly as a function of the substrate. For MnBr2 grown on Ir(110) the largest number of polaron species is observed, namely four, of which three show clear similarities with the species observed for CoCl2 on graphite. Polarons in single-layer MnBr2 are observed up to 300K. They can be created, converted, and moved by the STM tip when a tunneling current flows at a proper bias voltage. For graphene on Ir(110) as a substrate, mobile polarons in MnBr2 are guided through the periodic potential imposed from the super-moiré resulting from the interaction of MnBr2 with graphene and Ir(110). Our findings indicate that modeling of polarons in such single-layer insulators in contact with a conducting substrate requires to take the substrate explicitly into account.