Investigation of the nonlinear CPT spectrum of 87Rb and its application for large dynamic magnetic measurement*

Project supported by the National Natural Science Foundation of China (Grant No. 61473166) and China Postdoctoral Science Foundation (Grant No. 014M560958).
Xu Chi1, 2, Wang Shi-Guang2, 3, Hu Yong2, 3, Feng Yan-Ying2, 3, †, Wang Li-Jun1, 2, 3, ‡
       

(color online) (a) Linear CPT spectrum observed in the lin ∥ lin configure. The FWHM (full width at half maximum) of the peak at 100 kHz is about 1 kHz (dash line: , solid line: ). Insert: nonlinear split of the N = +2 at a magnetic field about 280 mGs. This spectrum is observed at a relatively low light intensity with an FWHM of 600 Hz. (b) Nonlinear split of the magnetic insensitive CPT resonant peaks. Observation of the two re-split resonant peaks (solid line) in group N = 0 at a large magnetic field, together with their error signal (dash line) after the lock-in amplifier in the control Section 2. The resonant peak at the middle is almost covered by noise due to destructive interference.