Biaxial strain effect on the electronic structure and valleytronic properties of a MoS₂/CoO(111) heterostructure

Abstract

Spin splitting, valley splitting and Berry curvature at the K and K′ valleys of a MoS2/CoO(111) heterostructure can be tuned continually by biaxial tensile strain.

Enhancement and modulation of valley polarization in Janus CrSSe with internal and external electric fields

“…Moreover, it is clear that the value of Berry curvature has decreased significantly from CrSSe to CrSSe/MnO 2 , which is similar to the decrease in MoS 2 and MoS 2 /CoO. 59 The decrease is mainly due to the increase in the bandgap from 0.79 eV for CrSSe to 1.16 eV for CrSSe/MnO 2 as shown in the layer-resolved band structure in Fig. S3 (ESI †).…”

Tuning the Photoluminescence and Raman Response of Single-Layer WS2 Crystals Using Biaxial Strain

“…Additionally, a direct-to-indirect transition occurs upon application of tensile strain. − Moreover, anisotropic types of strain (e.g., uniaxial or pure shear) reduce the crystal symmetry and also affect the curvature of the conduction and valence bands (i.e., the carrier effective masses) . Furthermore, experimentally feasible mechanical strains (≤0.5%) were found to affect considerably the exciton kinetics and intervalley scattering mechanisms in 2D TMDCs, indicating the possibility of strain-modulated valleytronic devices . The implications of isotropic and anisotropic strains on 2D material-based devices have been recently demonstrated in strain-tunable monolayer (1L) MoS 2 photodetectors. , …”

“…36 Furthermore, experimentally feasible mechanical strains (≤0.5%) were found to affect considerably the exciton kinetics and intervalley scattering mechanisms in 2D TMDCs, 30 indicating the possibility of strain-modulated valleytronic devices. 37 The implications of isotropic and anisotropic strains on 2D material-based devices have been recently demonstrated in strain-tunable monolayer (1L) MoS 2 photodetectors. 38,39 Due to their vanishing thickness, application of mechanical strain in 2D crystals is not as straightforward as in bulk materials, which can be directly clamped to a mechanical testing apparatus.…”

Mechanisms of manipulating valley splitting in MoTe2/MnS2 van der Waals heterostructure by electric field and strains

“…In-plane strain is also a useful method for controlling the electronic characteristics of heterostructures and can be performed through substrate tensile or bending. 56–58 Biaxial strain can be defined using the following equation: ε = ( a − a 0 )/ a 0 , which refers to the relative difference in the lattice constants before and after applying biaxial strain. a 0 is the lattice constant without the applied strain.…”