Ultrafast Depopulation of a Quantum Dot by LA-phonon-assisted Stimulated   Emission
  We demonstrate ultrafast incoherent depopulation of a quantum dot from above to below the transparency point using LA-phonon-assisted emission stimulated by a redshifted laser pulse. The QD is turned from a weakly vibronic system into a strongly vibronic one by laser driving which enables the phonon-assisted relaxation between the excitonic components of two dressed states. The depopulation is achieved within a laser pulse-width-limited time of 20 ps and exhibits a broad tuning range of a few meV. Our experimental results are well reproduced by path-integral calculations. 
F. Liu, L. M. P. Martins, A. J. Brash, A. M. Barth, J. H. Quilter, V.   M. Axt, M. S. Skolnick and A. M. Fox
cond-mat.mes-hall