Twistronics: Manipulating the electronic properties of two-dimensional layered structures through their twist angle

Abstract

The ability in experiments to control the relative twist angle between successive layers in twodimensional (2D) materials offers a new approach to manipulating their electronic properties; we refer to this approach as "twistronics". A major challenge to theory is that, for arbitrary twist angles, the resulting structure involves incommensurate (aperiodic) 2D lattices. Here, we present a general method for the calculation of the electronic density of states of aperiodic 2D layered materials, using parameter-free hamiltonians derived from ab initio density-functional theory. We use graphene, a semimetal, and MoS2, a representative of the transition metal dichalcogenide (TMDC) family of 2D semiconductors, to illustrate the application of our method, which enables fast and efficient simulation of multi-layered stacks in the presence of local disorder and external fields. We comment on the interesting features of their Density of States (DoS) as a function of twist-angle and local configuration and on how these features can be experimentally observed.

Moiré Potential, Lattice Corrugation, and Band Gap Spatial Variation in a Twist-Free MoTe2/MoS2 Heterobilayer

“…Note that data for Mo located at AA, AB, and BA are plotted in bold curves to add emphasis. To make the displacement of LDOS curves more visible, we follow Carr et al [6] to make use of the logarithm of LDOS (bottom panel) to estimate VBM and CBM for a selected number of Mo atoms.…”

Induced spin-orbit coupling in twisted graphene–transition metal dichalcogenide heterobilayers: Twistronics meets spintronics

“…As a concrete example we consider graphene on monolayer MoS 2 , but the same approach can be used for other semiconductor monolayer TMDC where the Dirac point of graphene is in the band gap of the substrate. The possibility to tune the strength of the induced SOC in graphene by changing the interlayer twist angle links graphene spintronics with the newly emerging field of twistronics [39][40][41][42] .…”

Efficient computation of Kubo conductivity for incommensurate 2D heterostructures

“…The electronic structure of incommensurate bilayers has become a hot topic, particularly after the discovery of superconductivity in bilayer graphene with a relative twist at the so called magic angle [3]. Twistronics, the tuning of electronic structure by twisting stacks of 2D materials, gives a new set of parameters for tuning electronic structure, expanding the possible set of applications of these materials [4,11].…”