Fig. 3. Single-photon experiments.

a Lifetime measurements using our device (purple) compared to commercial fiber–coupled SNSPDs (black). Inset: spectrum of the deterministically excited quantum dot used in this work, under π pulse excitation, with highlighted exciton (X) and biexciton (XX) lines. b HBT measurements, showing a comparison of detection off-chip (top) and detection with one SNSPD on-chip (bottom). c Sketch outlining the experimental configuration. For a the lifetime of the QD is either fully measured on-chip or using the commercial SNSPD system. For b one arm of the HBT setup is on-chip while the second arm is connected to the SNSPD system. The coincidences are then measured using a time-to-digital converter. Optical components: BS beam splitter, NF notch filter, TG transmission grating, POL polarizer, ($\frac{\lambda }{2}$) half waveplate, DUT device under test.