Timing Jitter Characterization of Dual-Comb Time and Frequency Transfer System for Precision Dissemination of Optical Frequency Standard

Abstract

Time and frequency transfer via asynchronous optical sampling technique benefitting from dual-comb system owning unprecedented high precision has shown an attractive potential in ultra-precision spatial and temporal reference frame establishment in future. Mutual phase coherence is the utmost crucial factor in asynchronous optical sampling. Here we report a dual-comb asynchronous optical sampling system with a low residual optical phase jitter less than 0.04 rad in a noise band from 1 Hz to 5 MHz around 1.55 μm, which implies a timing jitter at around 30 as. The Fourier frequency, at which the residual phase jitter reaches 1 rad, is between 0.06 Hz and 0.1 Hz. Therefore, the coherence time is greater than 10 s. The residual frequency stability of the system reaches 1.2 ×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-16</sup> at an averaging time of 1 s.