Implementation of a loss-compensated recirculating delayed self-heterodyne interferometer for ultranarrow laser linewidth measurement

Ultranarrow laser linewidth measurement using an optimized loss-compensated recirculating delayed self-heterodyne interferometer is described. An experimental setup is constructed to measure subkilohertz laser linewidths. The system parameters are optimized to obtain the best beat signals. The experimental results agree well with the theoretical analysis. Two methods of linewidth interpretation are presented and analyzed based on the experimental results. It is proved that a loss-compensated recirculating delayed self-heterodyne interferometer is an effective tool for measuring an ultranarrow laser linewidth. (c) 2006 Optical Society of America.