Coherent control of NV⁻centers in diamond in a quantum teaching lab

The room temperature compatibility of the negatively-charged nitrogen-vacancy (NV⁻) in diamond makes it the ideal quantum system for a university teaching lab. Here, we describe a low-cost experimental setup for coherent control experiments on the electronic spin state of the NV⁻ center. We implement spin-relaxation measurements, optically-detected magnetic resonance, Rabi oscillations, and dynamical decoupling sequences on an ensemble of NV⁻ centers. Hyperfine interactions can also be observed clearly in the measurement. The relatively short time required to perform each of these experiments (<10 minutes) demonstrates the feasibility of the setup in a teaching lab. Learning outcomes include a basic understanding of quantum spin systems, magnetic resonance, the rotating frame, Bloch spheres, and pulse sequence development