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. [ABSTRACT FROM AUTHOR]