Phase Locking of Semiconductor Lasers Using Homodyne Detection and Negative Electrical Feedback

Abstract

Investigations of an optical phase locked loop using semiconductor lasers and homodyne detection are reported. The phase noise in the phase locked loop, that is, the fluctuatin of phase difference between the slave and master laser is measured under free running and locked conditins. Strong phase noise reduction has been observed under locked condition. The measured results are in reasonable agreement with calculated results applying the linear transfer function of a phase locked loop.