Phase Recovery and Stability: Arbitrary Phase Access for Stable Fiber Interferometers (Laser Photonics Rev. 15(7)/2021)

Practical systems for optical interference are critical to coherent signal processing in devices and networks. In article number 2000524, Roberto Morandotti, Michael Kues, and co‐workers demonstrate an easily‐deployable scheme for the retrieval of relative phase in fiber interferometric systems. The use of bright and dim/photon‐level reference signals is contrasted, with pulsed references shown to enable temporal multiplexing with quantum signals.