Development Of Co-Located Xe-129 And Xe-131 Nuclear Spin Masers With External Feedback Scheme

We report on the operation of co-located Xe-129 and Xe-131 nuclear spin masers with an external feedback scheme, and discuss the use of Xe-131 as a comagnetometer in measurements of the Xe-129 spin precession frequency. By applying a correction based on the observed change in the Xe-131 frequency, the frequency instability due to magnetic field and cell temperature drifts are eliminated by two orders of magnitude. The frequency precision of 6.2 mu Hz is obtained for a 10(4) s averaging time, suggesting the possibility of future improliement to approximate to 1 nHz by improving the signal-to-noise ratio of the observation. (C) 2017 Elsevier B.V. All rights reserved.