Hydrostatic pressure and coupling-barrier effects on the cyclotron effective mass and Landé [formula omitted] factor in GaAs–Ga1−xAlxAs double coupled quantum wells

Abstract

Coupling-barrier in between GaAs quantum wells and the applied hydrostatic pressure effects on the conduction electron cyclotron effective mass and Landé g∥ factor under a growth-direction applied magnetic field in strongly coupled and uncoupled GaAs-Ga1−xAlxAs QWs are investigated. Numerical calculations are performed within the effective mass approximation and taking into account the anisotropy and non-parabolicity effects for the conduction-band electrons, by means of the Ogg–McCombe effective Hamiltonian. The system consists of two GaAs quantum wells connected by a Ga1−xAlxAs barrier and surrounded by Ga1−yAlyAs material. As a result, the behavior of the band parameters m⁎ and g as a function of the applied hydrostatic pressure are sensitive for “small” values of the central barrier width LB, and for large values the behavior occurs as in a single QW. The coupling-barrier effect is studied by varying the Al concentration in the central barrier, after finding that there is a value of the Al concentration for which the cyclotron effective mass m⁎ and Landé g∥ factor converge to the same value due to the combined non-parabolicity, anisotropy and coupling-barrier effects.