GROWTH OF ND:LAF<V>3<D> CRYSTALS FOR DIODE LASER PUMPING

IT IS NECESSARY TO EVALUATE NEW LASER MATERIALS WITH INCREASED WALL PLUG EFFICIENCY. CURRENTLY SEMICONDUCTOR LASER ARRAYS HOLD THE POTENTIAL TO BE EFFECTIVE OPTICAL PUMPING SOURCES. IN ORDER TO UTILIZE THE SEMICONDUCTOR ARRAYS EFFECTIVELY, IT IS NECESSARY TO HAVE LASER MATERIALS WITH LONGER UPPER LEVEL LASER LIFETIME THAN THE COMMONLY USED ND:YAG LASER. THE PRESENT PROPOSAL IS TO ESTABLISH FEASIBILITY FOR THE GROWTH OF ND:LAF3 CRYSTALS USING THE HEAT EXCHANGER METHOD (HEM TM). THESE CRYSTALS HAVE SHOWN A LIFETIME OF 670 MICROSECONDS AND INTERESTING HIGH TEMPERATURE LASER PROPERTIES. THE CRYSTALS GROWN BY THE STOCKBARGER, BRIDGMAN AND CZOCHRALSKI TECHNIQUES HAVE BEEN LIMITED BY THEIR POOR OPTICAL QUALITY. THE SUBMERGED SOLID-LIQUID INTERFACE AND FLEXIBILITY OF ATMOSPHERE CONTROLDURING CRYSTAL GROWTH WITH HEM ARE EXPECTED TO YIELD A HIGH OPTICAL QUALITY ND:LAF3 CRYSTALS. IT IS INTENDED TO ESTABLISH FEASIBILITY OF GROWING ND:LAF3 CRYSTALS FOR LASER APPLICATIONS. EMPHASIS WILL BE PLACED ON MINIMIZING THE CONTAMINATION FROM THE OXIDE AND HYDROXYL IONS WHICH IS KNOWN TO DEGRADE THE OPTICAL QUALITY OF THESE CRYSTALS. THEGROWN CRYSTALS WILL BE CHARACTERIZED FOR OPTICAL QUALITY ANDLASER PERFORMANCE.