  The emerging hybrid integrated quantum photonics combines advantages of
different functional components into a single chip to meet the stringent
requirements for quantum information processing. Despite the tremendous
progress in hybrid integrations of III-V quantum emitters with silicon-based
photonic circuits and superconducting single-photon detectors, on-chip optical
excitations of quantum emitters via miniaturized lasers towards single-photon
sources (SPSs) with low power consumptions, small device footprints and
excellent coherence properties is highly desirable yet illusive. In this work,
we present realizations of bright semiconductor singe-photon sources
heterogeneously integrated with on-chip electrically-injected microlasers.
Different from previous one-by-one transfer printing technique implemented in
hybrid quantum dot (QD) photonic devices, multiple deterministically coupled
QD-circular Bragg Grating (CBG) SPSs were integrated with electrically-injected
micropillar lasers at one time via a potentially scalable transfer printing
process assisted by the wide-field photoluminescence (PL) imaging technique.
Optically pumped by electrically-injected microlasers, pure single photons are
generated with a high-brightness of a count rate of 3.8 M/s and an extraction
efficiency of 25.44%. Such a high-brightness is due to the enhancement by the
cavity mode of the CBG, which is confirmed by a Purcell factor of 2.5. Our work
provides a powerful tool for advancing hybrid integrated quantum photonics in
general and boosts the developments for realizing highly-compact,
energy-efficient and coherent SPSs in particular.
