Tunable parametric downconverter with photon-conversion efficiencies greater than 100%

We have demonstrated, for the first time to our knowledge, operation of a synchronously pumped optical parametric oscillator-difference frequency mixing (OPO-DFM) device. The OPO-DFM device is designed to maximize power-conversion efficiency from the pump to the idler in the mid-infrared. The OPO-DFM device has the same threshold as the OPO and operates with an idler photon-conversion efficiency over one, producing 80% more idler radiation than the OPO.