Extended Data Fig. 5: The thulium–zinc germanium phosphide OPO comb.
From: Modulated ringdown comb interferometry for sensing of highly complex gases
a, The OPO cavity geometry. Cavity mirrors are labelled M1–M6. Pump light is injected from M1 and idler light is out-coupled from M4. Coarse and fine cavity length control are achieved with a picomotor and a piezo mounted on M5 and M6, respectively. b, Power dependence measured for the idler on the pump, when the idler is tuned to 2,040 cm−1. The highest idler average power of 214 mW is measured at the pump power of 1,530 mW. The threshold pump power is 340(50) mW. Slope power efficiency is 19(1)% and photon conversion efficiency is 49(2)%. c, Table summarizing the crystal and mirrors specifications. AOI, angle of incidence; ROC, radius of curvature.
