News
Timekeeping with Electronic Spin States in Diamond
Frequency standards based on atomic states, such as Rb or Cs vapors, or single-trapped ions, are the most precise measures of time. We proposed and analyzed a precision oscillator approach based upon spins in a solid-state system, in particular, the nitrogen-vacancy defect in single-crystal diamond. We showed that that system could have stability that approached portable atomic standards and was readily incorporable as a chip-scale device. Through use of a pulsed spin-echo technique, we anticipated an Allan deviation of σy = 10−7τ −1/2 limited by thermally-induced strain variations; in the absence of such thermal fluctuations, the system was limited by spin dephasing and harbored an Allan deviation nearing ~10−12 τ −1/2. Potential improvements based upon advanced diamond material processing, temperature stabilization, and nanophotonic engineering were discussed.