Experimental comparison of two phase-insensitive amplifiers in practical applications: measure-and-prepare strategy vs. nonlinear parametric process

Four-wave mixing (FWM) and the measure-and-prepare (M-P) strategy are two widely adopted approaches for implementing optical phase-insensitive amplifiers (OPIAs). In this paper, we theoretically analyze and experimentally compare the performance of FWM-based and M-P-based OPIAs in practical scenarios. Due to the distinct nature of their implementations, these two schemes exhibit different levels of robustness against loss. The performance of the FWM process is primarily constrained by atomic absorption loss, particularly in the low-gain regime. In contrast, the M-P strategy is more sensitive to optical path attenuation occurring after signal amplification than to losses due to the inefficiencies of the homodyne detection stage.