Puzzling results explained: a multiband approach to Coulomb drag and indirect excitons in dual-layer graphene

Puzzling results explained: a multiband approach to Coulomb drag and indirect excitons in dual-layer graphene



A theoretical collaborative study by the University of Antwerp (Belgium), the University of Camerino (Italy) and the University of New South Wales (Australia) has explained previously mystifying experimental results obtained independently by two research groups in the USA, which showed coupled holes and electrons in dual-layer graphene structures sometimes moved in exactly the opposite direction to that predicted.

A multiband approach to Coulomb drag and indirect excitons in dual-layer graphene imageDevice schematic: one sheet of conductive bilayer graphene carries electrons, the other, separated by insulating hBN, carries holes

The new work showed that this apparently contradictory phenomenon is associated with the bandgap in dual-layer graphene structures, a bandgap which is very much smaller than in conventional semiconductors.

https://www.graphene-info.com/puzzling-results-explained-multiband-approach-coulomb-drag-and-indirect-excitons-dual-layer-graphene