Measurement noise floor for a long-distance optical carrier transmission via fiber

TL;DR

This paper investigates the measurement noise floor and stability of long-distance optical frequency transfer via fiber, achieving extremely low instability levels over 147 km of deployed fiber.

Contribution

It provides a detailed analysis of the measurement noise floor and demonstrates near-delay-limited stability for ultra-stable optical frequency transfer over long fiber links.

Findings

Achieved a measurement instability of 3x10^(-15)/(tau x Hz) over 147 km fiber

Reached a noise floor of 10^(-20) at 4000 seconds integration time

Demonstrated link stability suitable for high-precision optical frequency transfer

Abstract

We investigated the measurement floor and link stability for the transfer of an ultra-stable optical frequency via an optical fiber link. We achieved a near-delay-limited instability of 3x10^(-15)/(tau x Hz) for 147 km deployed fiber, and 10^(-20) (integrations time tau = 4000 s) for the noise floor.