High-stability and multithreading phase-coherent receiver for simultaneous transfer of stabilized optical and radio frequencies.

We demonstrate a high-stability and multithreading coherent receiver for simultaneous distribution of stabilized optical and radio frequencies (RFs). The technique is based on a monolithic electroabsorption modulator integrated with a distributed feedback laser, which can purify and amplify the optical carrier while recovering the RF signal as a high-speed photodetector. The large-dynamic-range and high-bandwidth phase-locking system preserves the stability of the receiver for optical and RF signals to 3.5 x 10(-20) and 6.4 x 10(-18) at 1000 s, respectively. Furthermore, a dual-stabilization system using this novel receiver is proposed for simultaneous transfer of ultrastable optical carriers and RF signals over a 263 km fiber link. The transferred frequency stabilities of the optical carrier and the 9.1 GHz signal are 6.5 x 10(-20) and 1.6 x 10(-17), respectively, for an averaging time of 10,000 s. (C) 2019 Optical Society of America