Optical properties of potential-inserted quantum wells in the near infrared and Terahertz ranges

We propose an engineering of the optical properties of GaAs/AlGaAs quantum wells using AlAs and InAs monolayer insertions. A quantitative study of the effects of the monolayer position and the well thickness on the interband and intersubband transitions, based on the extended-basis sp(3)d(5)s* tight-binding model, is presented. The effect of insertion on the interband transitions is compared with existing experimental data. As for intersubband transitions, we show that in a GaAs/AlGaAs quantum well including two AlAs and one InAs insertions, a three level {e(1), e(2), e(3)} system where the transition energy e(3)-e(2) is lower and the transition energy e(2)-e(1) larger than the longitudinal optical phonon energy (36 meV) can be engineered together with a e(3)-e(2) transition energy widely tunable through the TeraHertz range. (C) 2016 Elsevier Ltd. All rights reserved.