Intersublevel emission in InAs/GaAs quantum dots

We have observed intersublevel emission in InAs/GaAs self-assembled quantum dots. The midinfrared emission is spectrally resolved in the 90-185 meV spectral range. Population of the excited levels is achieved by non-resonant interband optical pumping in the wetting layer. Several emission lines are evidenced depending on the selected polarization. They are attributed to intersublevel transitions in the valence band of the dots. The selective Pauli blocking of the emission is demonstrated at high pump intensity when the ground state of the dots is filled up with two holes. The assignment of the emission lines to specific intersublevel transitions is based on the Pauli blocking of the emission and on the electronic structure given by the resolution of the three-dimensional Schrodinger equation in the effective-mass approximation.