We explain the strong interlayer drag resistances observed at low-temperatures in bilayer electron-hole systems in terms of an interplay between local electron-hole-pair condensation and disorder-induced carrier density variations. Smooth disorder drives the condensate into a granulated phase in which interlayer coherence is formed only in well separated disconnected regions, or grains, within which the densities of electrons and holes accidentally match. The drag resistance is then dominated by Andreev scattering of charge carries between layers at the grains that transfers momentum
About the presenter
Dr Hong Liu is currently working with CI Nikhil Medhekar and AI Dmitry Efimkin, exploring spin-orbit coupling and interaction effect in topological materials theoretically. As a member of Research theme 1 team, she aims to understand the criteria for protection against dissipation and also include the operational criteria for achieving dissipationless transport.