Atomistic tight-binding theory of multiexciton complexes in a self-assembled InAs quantum dot

作者：Zielinski M^*; Korkusinski M; Hawrylak P

来源：Physical Review B, 2010, 81(8): 085301.

DOI：10.1103/PhysRevB.81.085301

We present atomistic tight-binding theory of electronic structure and optical properties of InAs/GaAs self-assembled quantum dots. The tight-binding model includes zincblende symmetry, faceting, and sp(3)d(5)s* atomic orbitals accounting for interband and intervalley couplings. The equilibrium positions of atoms are calculated using valence force field method and modification of the tight-binding Hamiltonian due to strain is accounted for using Harrison's law. The electronic and optical properties of multiexciton complexes are then determined by diagonalizing the many-body Hamiltonian for interacting electrons and holes using the configuration-interaction approach. The calculations of strain distribution approach 10(8) atoms while the electron and valence hole single-particle states are calculated by diagonalization of the Hamiltonian matrix with size on the order of 10(7). The dependence of predicted electronic and optical properties on InAs/GaAs valence-band offset and InAs absolute valence-band deformation potentials are described. The reliability of the atomistic calculations is assessed by comparison with results obtained from the effective bond orbital model and empirical pseudopotentials method.

• 出版日期2010-2