We give instructions for the construction and operation of a simple apparatus for performing optically detected magnetic resonance measurements on diamond samples containing high concentrations of nitrogen-vacancy (NV) centers. Each NV center has a spin degree of freedom that can be manipulated and monitored by a combination of visible and microwave radiation. We observe Zeeman shifts in the presence of small external magnetic fields and describe a simple method to optically measure magnetic field strengths with a spatial resolution of several microns. The activities described are suitable for use in an advanced undergraduate lab course, powerfully connecting core quantum concepts to cutting edge applications. An even simpler setup, appropriate for use in more introductory settings, is also presented.

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Element Six sells HPHT diamond with suitably high nitrogen concentrations. See Ref. 31 for more detailed guidance on creating high NV concentrations in such samples via electron irradiation and annealing.

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This write-up tends to evolve over time as we discover ways in which the lab can be improved. For the latest version please contact the corresponding author at rberg@wellesley.edu.
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See Supplementary Material at https://doi.org/10.1119/1.5023389 for the Spring, 2018 version of the lab write-up.

Supplementary Material

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