Bichromatic dressing of a quantum dot detected by a remote second quantum dot

We demonstrate an information transfer mechanism between two dissimilar remote InAs/GaAs quantum dots weakly coupled to a common photonic crystal microcavity. Bichromatic excitation in the $s$ state of one of the dots leads to the formation of dressed states due to the coherent coupling to the laser field, in resonance with the quantum dot. Information on the resulting dressed structure is read out through the photoluminescence spectrum of the other quantum dot, as well as the cavity mode. The effect is also observed upon exchange of the excitation and detection quantum dots. This quantum dot intertalk is interpreted in terms of a cavity-mediated coupling involving acoustic phonons. A master equation for a three-level system coherently pumped by the two lasers quantitatively describes the behavior of our system. Our result presents an important step towards scalable solid-state quantum networking based on coupled multi-quantum-dot-cavity systems, without the need to use identical quantum emitters.