Observing hyperfine interactions of NV− centers in diamond in an advanced quantum teaching lab

The negatively charged nitrogen-vacancy (NV−) center in diamond is a model quantum system for university teaching labs due to its room-temperature compatibility and cost-effective operation. Based on the low-cost experimental setup that we have developed and described for the coherent control of the electronic spin [Sewani et al., Am. J. Phys. 88, 1156–1169 (2020)], we introduce and explain here a number of more advanced experiments that probe the electron–nuclear interaction between the NV− electronic and the 14N and 13C nuclear spins. Optically detected magnetic resonance, Rabi oscillations, Ramsey fringe experiments, and Hahn echo sequences are implemented to demonstrate how the nuclear spins interact with the electron spins. Most experiments only require 15 min of measurement time and, therefore, can be completed within one teaching lab.