Switching suppression and enhancement of fluorescence and six-wave mixing by phase modulation

The conversion between enhancement and suppression in six-wave mixing (SWM) and fluorescence signals by phase modulation has demonstrated for the first time. It is observed in our experiment the suppression of SWM and fluorescence is transformed into enhancement in company with the switch from electromagnetically induced transparency (EIT) to electromagnetically induced absorption (EIA) in the transmitted probe with the relative phase changed from 0 to π/2. Our research could be potentially applied in optical communication and quantum information processing.