Guided spontaneous emission circuit technique with improved optical power resolutions for optical power variation measurement

This study proposes a novel technique called the guided spontaneous emission circuit (GSEC) technique that can largely enhance the optical power resolution (OPR) of optical power variation measurement systems. The improvement factor (IF) in the OPR achieved by the GSEC technique is determined by the slope of the nonlinear optical input-output curve in dBm of the GSEC. Through experimental analyses, we clarified the characteristics of the IF and successfully optimized it by implementing a two-stage GSEC with two erbium-doped fibers (EDFs) and two optical filters. By optimizing the configuration of the two-stage GSEC, we achieved an optimized IF of approximately 30.6.