Vector detection of ac magnetic fields by nitrogen vacancy centers of single orientation in diamond

Nitrogen vacancy (NV) centers in diamond are highly sensitive nanoscale sensors of dc and ac magnetic fields. Vector detection of ac magnetic fields, where both strength and orientation of the applied field is determined, requires at least three NV centers of different orientations by the conventional method. Here, the authors propose and demonstrate a method for vector detection of ac magnetic fields by using NV centers having a single orientation. This method is equally applicable for single NV centers.