Phase Sensitive Amplifier Based on Ultrashort Pump Pulses
  We demonstrate a narrow band phase sensitive amplifier in the pump degenerate configuration which employs ps pump pulses. Control of the amplifier bandwidth is achieved via changes of the pump spectral width. A phase sensitive gain between -6 and 6 decibels, with an overall system gain of 28dB was demonstrated. 
Alexander Gershikov and Gad Eisenstein
physics.optics