Phase-Sensitive Detection of Raman-Enhanced Nondegenerate Four-Wave Mixing by Polarization Interference

We demonstrated a phase-sensitive method for studying the Raman-enhanced nondegenerate four-wave mixing (RENFWM). The reference beam is another four-wave mixing signal, which propagates along the same optical path as the RENFWM signal. This method is used for studying the phase dispersion of the third-order susceptibility x⁽³⁾ and for the optical heterodyne detection of the RENFW signal.