A new optical frequency transfer method via fibre based on active phase noise compensation with single acousto-optic modulator

In this paper, we propose and experimentally demonstrate a new method for optical frequency transfer over fibre. Instead of dual acousto-optic modulators (AOMs) as adopted in the traditional fibre phase noise compensation setup, here an active fibre phase noise compensation scheme with a single acousto-optic modulator (AOM) is used. The configuration simplifies the equipment of the user end while maintaining a high-performance optical frequency transfer stability. We demonstrate an actively stabilized coherent transfer at an optical frequency of 193.55THz over 10-km spooled fibre, obtaining a relative frequency stability (Allan deviation) of 3.84 x 10-16/1 s and 4.08 x 10-18/104 s, which is improved by about 2~3 orders of magnitude in comparison with the one without any phase noise compensation that achieves a relative frequency stability of 1.81 x 10-14/1 s and 2.48 x 10-15/104 s