Rashba splitting of Dirac points and symmetry breaking in strained artificial graphene

The effect of Rashba spin-orbit interaction and anisotropic elastic strain on the electronic, optical, and thermodynamic properties of an artificial graphenelike superlattice composed of InAs/GaAs quantum dots has been theoretically considered. The electronic energy dispersions have been obtained using Green's function formalism in combination with the Fourier transformation to the reciprocal space and an exact diagonalization technique. We have observed a splitting of Dirac points and the appearance of additional Dirac-like points due to the Rashba spin-orbit interaction. Furthermore, a breaking of the hexagonal symmetry of the dispersion surfaces caused by the strain anisotropy is observed as well. It is shown that both the spin-orbit interaction and strain anisotropy have a qualitative impact on the measurable characteristics of the considered structure and can be used as effective tools to control the performance of devices based on artificial graphene.