We present an analysis of pulse propagation under conditions of electromagnetically induced transparency and four-wave mixing in hot Rb vapor. We experimentally and theoretically investigate the prospect of dual-mode light storage.
We study procedures for the optimization of efficiency of light storage and retrieval based on the dynamic form of electromagnetically induced transparency in hot Rb vapor. We present a detailed analysis of two recently demonstrated optimization protocols: a time-reversal-based iteration procedure, which finds the optimal input signal pulse shape for any given control field, and a procedure based on the calculation of an optimal control field for any given signal pulse shape. We verify that the two procedures are mutually consistent and that they both independently achieve the maximum memory efficiency for any given optical depth. We observe good agreement with theoretical predictions for moderate optical depths (<25), while at higher optical depths the experimental efficiency falls below the theoretically predicted values. We identify possible effects responsible for this reduction in memory efficiency.