Effects of photo-neutralization on the emission properties of quantum   dots
  In this paper we investigate the coherence properties of a quantum dot under two-photon resonant excitation in combination with an additional photo-neutralization laser. The photo-neutralization increases the efficiency of the excitation process and thus, the brightness of the source, by a factor of approximately 1.5 for biexciton-exciton pairs. This enhancement does not degrade the relevant coherences in the system; neither the single photon coherence time, nor the coherence of the excitation process. 
Tobias Huber and Ana Predojevi\'c and Glenn S. Solomon and Gregor   Weihs
quant-ph cond-mat.mes-hall