NV Center Detection of Electric Fields and Low-Intensity Light*

Nitrogen vacancy (NV) center spins in diamond are attractive candidates for quantum information processing and sensitive, nanoscale magnetometers due to their long spin coherence times under ambient conditions [1]. The ground state of the NV spin is also sensitive to electric fields [2]. We present a theory of quantum detection using positive operator valued measurements wherein the presence of an electric field is determined by spin-dependent fluorescence of an NV center. The predicted sensitivity to small electric fields can also be used for photon detection. Photons incident upon a chromophore near the diamond interface may induce a charge polarization and electric dipole moment of several Debye [3, 4]. The measured readout state from the NV center predicts the existence of the photo-excited electric dipole field and, by extension, the incident photon. We describe a measurement protocol by which the time of the incident photon can be resolved. We discuss the role of magnetic fields and multiple NV centers in reducing error rates.

[1] R. Hanson et al., Phys. Rev. B 74, 161203(R) (2006)
[2] F. Dolde et al., Nature Physics 7, 459 (2011)
[3] M. Kim et al., Nano Letters 12, 182 (2012)
[4] Zhao et al., ACS Appl. Mater. Interfaces, 5, 9355 (2013)