Investigation of interband optical transitions by near-resonant magneto-photoluminescence in InAs/GaAs quantum dots

Resonant photoluminescence experiments performed on self-assembled InAs/GaAs quantum dots under strong magnetic field up to 28 T give rise to an accurate determination of the interband magneto-optical transitions. As this technique minimizes the effect of the homogeneous broadening of the transitions due to the size and composition fluctuations of the dots, the experimental spectra display well-defined peaks. A good agreement is found between the experimental data and calculations using an effective mass model including the coupling between the mixed exciton-LO phonon states. Transitions involving excitonic polarons are clearly identified. Moreover, a light-hole to conduction transition is also evidenced in agreement with previous theoretical predictions