Phonon-assisted biexciton generation in a single quantum dot

Phonon-assisted absorption of a single InGaAs/GaAs quantum dot is investiga ted by multichannel photoluminescence excitation spectroscopy as a function of magnetic held. GaAs LO phonon-assisted generation of exciton and biexci ton states is observed. Magnetic held induced detuning of the resonance con ditions results in a twofold diagonal splitting of the exciton and a symmet ric fourfold splitting of the biexciton resonances. Those findings are expl ained in terms of sequential phonon-assisted biexciton generation followed by sequential biexciton decay.