Example of how spin packets in a condensed matter system can be accessed and studied, adapted from Kubo et al. . A diamond slab containing nitrogen-vacancy center spins (arrows) is positioned above a microfabricated superconducting resonator. A magnetic field BNV is applied as shown to tune the NV centers. A microwave signal excites a mode in the resonator with magnetic field Br to manipulate and probe the spin ensemble.