Tunable MID-IR Optical Parametric Oscillator Using Periodically Poled Rubidium Titanyl Arsenate
AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH SCHOOL OF ENGINEERING
Pagination or Media Count:
Tunable sources of coherent radiation are needed for a variety of military and commercial applications, including infrared countermeasures and atmospheric remote sensing. This research investigates a tunable mid-infrared coherent source using periodically-poled rubidium titanyl arsenate PPRTA as a quasi-phase matched QPM optical parametric oscillator OPO. The advantages of PPRTA over periodically poled lithium niobate PPLN are presented. Quasi-phase matching and periodic poling theory are discussed, along with some important historical results and current developments. Experimental setups for determining threshold, conversion efficiency, pump depletion, and beam quality are presented along with experimental results. The research effort is focused on characterizing PPRTA through the generation of tunable midinfrared laser radiation in the 1.4 to 4.0 micron region. Results successfully demonstrate PPRTA conversion in the 1.5 um range with a 173 mJ oscillation threshold and a beam quality M2 value of 9.0. Slope efficiency of PPRTA is shown to be 24, compared to slope efficiency of 15 for PPLN in an identical system setup. The high slope efficiency, high pump conversion approximately equal 60, absence of damage at pump levels in excess of 300 MW sq cm, and large aperture scaling possibilities suggest that PPRTA is well suited for higher power applications.
- Lasers and Masers
- Optical Countermeasures
- Infrared Detection and Detectors