Electronic and magnetic properties of the one-dimensional interfaces of two-dimensional lateral GeC/BP heterostructures

We studied the electronic and magnetic properties of one-dimensional (1D) interfaces of two dimensional (2D) GeC/BP lateral heterostructures by first-principles calculations. We showed that an inner electric field exists in the heterostructures, and the 1D interfaces exhibit metallic properties when the ribbon width is larger than a critical value. In other words, the 1DEG/1DHG (one dimensional electron gas/one dimensional hole gas) with pi bonding character appear at the interfaces. We verified that the existence of the polar discontinuity at the interfaces is the pre-requisite for this insulator-to-metal transition, which can be understood by the topology classification of the formal polarization of the honeycomb structures with C-3 symmetry and the corresponding charge compensation mechanism was also discussed. We predicted the emergence of magnetism at the interfaces, with the width-dependent spin polarization being attributed to the Stoner instability. Increasing DOS at the interfaces leads to a paramagnetic to ferromagnetic transition.