A Scalable Network Model for Electrically Tunable Ferroelectric Domain Structure in Twistronic Bilayers of Two-Dimensional Semiconductors

Vladimir V Enaldiev; Fabio Ferreira; Vladimir I Fal'ko

doi:10.1021/acs.nanolett.1c04210

A Scalable Network Model for Electrically Tunable Ferroelectric Domain Structure in Twistronic Bilayers of Two-Dimensional Semiconductors

Nano Lett. 2022 Feb 23;22(4):1534-1540. doi: 10.1021/acs.nanolett.1c04210. Epub 2022 Feb 7.

Authors

Vladimir V Enaldiev^{1

2

3}, Fabio Ferreira^{1

2}, Vladimir I Fal'ko^{1

2

4}

Affiliations

¹ University of Manchester, School of Physics and Astronomy, Oxford Road, Manchester M13 9PL, United Kingdom.
² National Graphene Institute, University of Manchester, Booth Street East, Manchester M13 9PL, United Kingdom.
³ Kotelnikov Institute of Radio-engineering and Electronics of the RAS, Mokhovaya 11-7, Moscow 125009, Russia.
⁴ Henry Royce Institute, University of Manchester, Booth Street East, Manchester M13 9PL, United Kingdom.

Abstract

Moiré structures in small-angle-twisted bilayers of two-dimensional (2D) semiconductors with a broken-symmetry interface form arrays of ferroelectric (FE) domains with periodically alternating out-of-plane polarization. Here, we propose a network theory for the tunability of such FE domain structure by applying an electric field perpendicular to the 2D crystal. Using multiscale analysis, we derive a fully parametrized string-theory-like description of the domain wall network (DWN) and show that it undergoes a qualitative change, after the arcs of partial dislocation (PD) like domain walls merge (near the network nodes) into streaks of perfect screw dislocations (PSD), which happens at a threshold displacement field dependent on the DWN period.

Keywords: Ferroelectrics; domain wall network; twistronic heterostructures; van der Waals heterostructures.