  A scalable on-chip single-photon source at telecommunications wavelengths is
an essential component of quantum communication networks. In this work, we
numerically construct a pulse-regulated single-photon source based on an
optical parametric amplifier in a nanocavity. Under the condition of pulsed
excitation, we study the photon statistics of the source using the Monte Carlo
wave-function method. The results show that there exits an optimum excitation
pulse width for generating high-purity single photons, while the source
brightness increases monotonically with increasing excitation pulse width. More
importantly, our system can be operated resonantly and we show that in this
case the oscillations in $g^{(2)}(0)$ is completely suppressed.
