We investigate both experimentally and theoretically a simple yet more robust and flexible alternative to Rabi oscillation-type biexciton preparation protocols traditionally used for semiconductor quantum dots. The quantum dot is excited by a strong laser pulse positively detuned from the two-photon resonance yielding an on demand initialization of the biexciton state by making use of the phonon-induced thermalization of the photon dressed states. It is shown that for excitation pulses in the picosecond range, a stable and high fidelity of up to fXX=0.98±0.01 is reached. Notably, the generated photons show similar coherence properties as measured in the resonant two-photon scheme. This protocol is a powerful tool for the control of complex solid state systems combining radiative cascades, entanglement and resonant cavity modes.
@article{arxiv.1408.7027,
title = {Phonon-assisted robust and deterministic two-photon biexciton preparation in a quantum dot},
author = {S. Bounouar and M. Müller and A. M. Barth and M. Glässl and V. M. Axt and P. Michler},
journal= {arXiv preprint arXiv:1408.7027},
year = {2015}
}