Fourier algorithm for four-wave-mixing signals from optically dense systems with memory

摘要

A triple Fourier-transform algorithm for generating and propagating femtosecond four-wave-mixing signals in optically thick samples is demonstrated. The algorithm has a dynamic range that is useful for tests of theory and simulations of experiments with an arbitrary nonlinear response. Although two-pulse echoes decay faster as optical density increases for a Bloch model, we find that systems with memory exhibit the opposite trend.