Resent progresses of dual-wavelength good-bad cavity active optical clock

We propose a dual-wavelength good-bad cavity active optical clock, of which the two output signals with different wavelength share the same cavity, and work in good cavity and bad cavity regime, respectively. The good cavity signal is locked to a super cavity by the PDH technique, and thus the main cavity length of the active optical clock is stabilized. The frequency stability of the clock signal is expected to be improved by 2 orders of magnitude than that of the PDH stabilized signal, due to the suppression of cavity pulling effect in the bad cavity. Experimentally, we take the Nd: YAG 1064 nm transition as good-cavity gain medium, and the bad-cavity signal works on Cs 1470 nm transition. The dual-wavelength output of the active optical clock is realized, and the power and linewidth characteristics are preliminarily studied.