Eur. Phys. J. D (2016) 70: 129
https://doi.org/10.1140/epjd/e2016-70034-8

Regular Article

Frequency characteristics of nuclear spin oscillator with an artificial feedback toward search for ¹²⁹Xe atomic electric dipole moment

¹ Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-okayama, Meguro, Tokyo 152-8551, Japan
² Research Institute for Interdisciplinary Science, Okayama University, 3-1-1 Tsushimanaka, Kita, Okayama 700-8530, Japan
³ RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
⁴ Department of Advanced Sciences, Hosei University, 3-7-2 Kajino-cho, Koganei, Tokyo 184-8584, Japan
⁵ Research Center for Nuclear Physics, Osaka University, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan

^a e-mail: inouet@cyric.tohoku.ac.jp
^b Present address: Frontier Research Institute for Interdisciplinary Sciences/Cyclotron and Radioisotope Center, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan.
^c Present address: Department of Physics, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji, Tokyo 192-0397, Japan.
^d Present address: RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.

Received: 18 January 2016
Received in final form: 28 March 2016
Published online: 7 June 2016

Abstract

A ¹²⁹Xe nuclear spin oscillator with an artificial feedback was constructed, and detailed studies were conducted on its performance, focusing on the frequency stability. As a result, the major sources of drift of the precession frequency in the present spin oscillator setup were identified to be drifts of a solenoid current and an environmental magnetic field. By introducing stabilization systems for the current and the environmental field, which yielded improvements by one order of magnitude on the solenoid current and by a factor of three on the environmental field, a frequency precision of 7.9 nHz was obtained for a one-shot measurement of 3 × 10⁴ s duration. We found, however, that the Allan deviation leveled off at around 30 μHz, indicating a strong need for the precision monitor of the experimental conditions represented by magnetometry. The frequency stability of the spin oscillator is discussed in relation to an experimental search for an electric dipole moment of the ¹²⁹Xe atom.