EXCITONS IN COMPLEX QUANTUM NANOSTRUCTURES

A theory for excitons in complex quantum nanostructures with complicat ed geometries and strong coupling between nanostructures is presented. Effective mass models with screened Coulomb interaction give reasonab le ground-state energies for excitons in T-shaped quantum wires, coupl ed T-quantum wires and quantum dot quantum wells, provided the effects of complex geometry are included. A sizable shift between exciton sta tes in quantum wells and T-shaped wires occurs due to a 40% enhancemen t in binding energy, confinement in the wire, and significant interwir e coupling.