Two-photon Rabi oscillations in a singleInxGa1−xAs∕GaAsquantum dot

Abstract

We report on Rabi oscillations of the biexciton in a single ${\mathrm{In}}_x{\mathrm{Ga}}_{1-x}\mathrm{As}∕\mathrm{Ga}\mathrm{As}$ quantum dot, induced via a coherent two-photon process. In contrast to single-exciton Rabi oscillations the measured population oscillation is not purely sinusoidal in excitation pulse area. The experimental results are well reproduced by a theoretical calculation that relies only on the pulse shape and biexciton binding energy. Dephasing times of the biexciton are similar to those of the single exciton under the applied measurement conditions reaching up to $220\mathrm{ps}$.