  The global quantum internet will require long-lived, telecommunications band
photon-matter interfaces manufactured at scale. Preliminary quantum networks
based upon photon-matter interfaces which meet a subset of these demands are
encouraging efforts to identify new high-performance alternatives. Silicon is
an ideal host for commercial-scale solid-state quantum technologies. It is
already an advanced platform within the global integrated photonics and
microelectronics industries, as well as host to record-setting long-lived spin
qubits. Despite the overwhelming potential of the silicon quantum platform, the
optical detection of individually addressable photon-spin interfaces in silicon
has remained elusive. In this work we produce tens of thousands of individually
addressable `$T$ centre' photon-spin qubits in integrated silicon photonic
structures, and characterize their spin-dependent telecommunications-band
optical transitions. These results unlock immediate opportunities to construct
silicon-integrated, telecommunications-band quantum information networks.
