Discovery of new misfit compounds for twistronic applications
Most of the crystalline solids are formed by the periodic arrangement of one or more types of atoms in three dimensions following particular spatial symmetries. However, some compounds are treated as two-dimensional because the bonding interactions along one direction is negligible compared to the strong in-plane bonds. Transition metal dichalcogenides constitute a family of two-dimensional compounds where the layers are held together by weak van der Waals interactions. One can also artificially stack alternate individual layers of two distinct layered compounds, for example, the so-called misfit compounds. In such structures, the periodicity in one direction of the layer is equal for alternate layers but in the other direction of the layers, it is incommensurate. The properties of the misfit compounds rely on the charge transfer between the constituent structural units; displaying semiconducting to superconducting behavior. The structural scenario can be related to the recent examples of twisted bilayer graphene wherein electronic structure is substantially modified by moiré superlattice and undergoes superconducting and ferromagnetic transitions. The aim of the project is to discover new misfit compounds, which unlike twisted bilayer graphene provide huge scope of chemical tenability to achieve desired exotic properties. Additionally, there is immense possibility to tweak the known misfit compounds by the use of external perturbations like uniaxial stress and strain towards boosting the twistronic applications.