Quantum state tomography measurements on strain‐tuned InxGa1−xAs/GaAs quantum dots
Klaus D. Jöns, R. Hafenbrak, P. Atkinson, Armando Rastelli, Oliver G. Schmidt, Peter Michler · physica status solidi (b) · 2012
Abstract We present quantum state tomography (QST) measurements on strain‐tuned self‐assembled InxGa1−xAs/GaAs quantum dots. By applying uniaxial stress we tune the fine structure splitting (FSS) of the exciton transition and investigate the change in the two‐photon polarization state (TPPS) of the quantum dot. We tune the FSS to a minimum value of 4.7 µeV. The density matrix of the TPPS indicates an onset of the anti‐crossing of the exciton transition. Our experiments show that strain‐tuning is a promising method for the generation of triggered polarization entangled photon pairs.