EXCITED STATE ABSORPTION PUMPED UPCONVERSION LASERS

WE PROPOSE A NEW UPCONVERSION PUMPING SCHEME CALLED EXCITED STATE ABSORPTION (ESA) PUMPING WHICH CAN BE DESCRIBED AS ATWO PHOTON RESONANT PUMPING PROCESS IN WHICH THE SECOND PHOTON IS INTERNALLY GENERATED (SIMILAR TO ION-PAIR INTERACTIONS IN WHICH THE ENERGY MAY BE TRANSFERRED WITHOUT PHOTON EMISSION). WE PROPOSE TO IDENTIFYPUMPING PATHS AND INVESTIGATE LASER OPERATION FOR BOTH ESA PUMPING AND PHOTON AVALANCHE UPCONVERSION IN ND:YLF AND ER:YLF. THESE TWO CLASSES OF UPCONVERSION LASERS OFFER THE POTENTIAL FOR NEW UPCONVERSION LASER WAVELENGTHS AND OPERATION AT HIGHER TEMPERATURES THAN MORE CONVENTIONAL MULTI-PHOTON PUMPED UPCONVERSION LASERS. ANTICIPATED BENEFITS/POTENTIAL COMMERCIAL APPLICATIONS - THE POTENTIAL APPLICATIONS FOR DIODE-PUMPED UPCONVERSION LASERS INCLUDE: 1) REPROGRAPHIC AND IMAGING APPLICATIONS REQUIRING COMPACT AND EFFICIENT SOURCES OF THE PRIMARY COLORS;2) SOURCES FOR USE IN OPTICAL STORAGE MEDIA THAT REQUIRE DIFFERENT BLUE AND NEAR-UV WAVELENGTHS FOR READ, WRITE, AND ERASE FUNCTIONS; AND 3) GENERAL SCIENTIFIC LASER SOURCE APPLICATIONS FOR THE SPECTROSCOPIC INVESTIGATION OF OTHER MATERIALS.