  The development of efficient quantum communication technologies depends on
the innovation in multiple layers of its implementation, a challenge we address
from the fundamental properties of the physical system at the nano-scale to the
instrumentation level at the macro-scale. We select a promising near infrared
quantum emitter, the nitrogen-vacancy (NV) center in 4H-SiC, and integrate it,
at an ensemble level, with nanopillar structures that enhance photon collection
efficiency into an objective lens. To characterize NV center properties at the
unprecedented sub-2 Kelvin temperatures, we incorporate compatible
superconducting nanowire single photon detectors inside the chamber of an
optical cryostat and create the ICECAP, the Integrated Cryogenic system for
Emission, Collection And Photon-detection. ICECAP measurements show no
significant linewidth broadening of NV ensemble emission and up to 28-fold
enhancement in collected emission. With additional filtering, we measure
emitter lifetimes of NV centers in a basal ($hk$) and an axial ($kk$)
orientation unveiling their cryogenic values of 2.21 ns and 2.86 ns.
