The Mollow triplets under few-photon excitation

Resonant excitation is an essential tool in the development of semiconductor quantum dots (QDs) for information processing. One central challenge to enable transparent access QD signal without post-selection loss. A viable path through cavity enhancement, which has successfully lifted resonantly scattered field strength over laser background under weak excitation. Here, we extend this success saturation regime using a QD-micropillar device with Purcell factor 10.9 and ultra-low reflectivity just 0.0089±0.0001. We achieve ratio 55 overall system responsivity 3.01±0.08%, i.e., detect on average 0.03 single photons every incident photon. Raising few-photon level, response brought into where observe Mollow triplets as well associated cascaded photon emissions, resorting any rejection technique. Our work offers perspective interface that not restricted by background.