Quantum well to quantum wire crossover in AlAs/GaAs/AlAs heterostructures induced by interface roughness increase

Adopting a real-space tight-binding supercell approach, we investigate inte rface roughness effects in semiconductor heterostructures, AlAs/GaAs/AlAs ( 001) QWs of average width W are considered, in which one of the interfaces is planar and the other has a shape defined by periodic steps with amplitud e A and wavelength lambda. The oscillator strength f of the fundamental tra nsition in the well describes the optical nature of the heterostructures, B y investigating the wavefunctions as a function of the interface parameter A, we conclude that the f behavior with A is an optical signature of the qu antum well to quantum wire crossover in the heterostructures, Recently, pho toluminescence experiments showed that hydrostatic pressure produces an inc rease in the optical efficiency of heterostructures in which the interfaces present a high degree of toughness. In order to investigate this optical b ehavior, we discuss hydrostatic pressure effects on rough-interface heteros tructures.