Two-dimensional electrons at mirror and twistronic twin boundaries in van der Waals ferroelectrics.

ABSTRACT: Semiconducting transition metal dichalcogenides (MX₂) occur in 2H and rhombohedral (3R) polytypes, respectively distinguished by anti-parallel and parallel orientation of consecutive monolayer lattices. In its bulk form, 3R-MX₂ is ferroelectric, hosting an out-of-plane electric polarisation, the direction of which is dictated by stacking. Here, we predict that twin boundaries, separating adjacent polarisation domains with reversed built-in electric fields, are able to host two-dimensional electrons and holes with an areal density reaching  ~ 10¹³cm^-2. Our modelling suggests that n-doped twin boundaries have a more promising binding energy than p-doped ones, whereas hole accumulation is stable at external surfaces of a twinned film. We also propos

SUBMITTER: McHugh JG 

PROVIDER: S-EPMC11316064 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature