SEMICONDUCTOR LASER EXCITED UPCONVERSION TRANSITIONS IN HOLMIUM (SLEUTH)

A BLUE-GREEN LASER IS PROPOSED WHICH IMPLEMENTS UPCONVERSION ENERGY TRANSFER PROCESSES TO EXCITE THE 5G6 5I8 LASER TRANSITION IN HO3+ IS HIGHLY PROMISING FOR SUBMARINE COMMUNICATIONS APPLICATIONS AS THE WAVELENGTH OF THIS TRANSITION IS EXTREMELY CLOSE TO THE 6S1/2 7P3/2 RESONANT ADSORPTION IN CESIUM (455.66NM). THE RESULTS OF CALCULATIONS APPLYING THE JUDD-OFELT APPROXIMATIONS INDICATE A LARGE OSCILLATOR STRENGTH CORRESPONDING TO THIS LASER TRANSITION. THE PROGRAM WILL INVESTIGATE 455 NM STIMULATED EMISSION IN HO:BAY2F8. THISHOST LATTICE IS PROMISING FOR UPCONVERSION PUMPING SINCE IT SUPPORTS UPCONVERSION VIA PAIR PROCESSES FOR EFFICIENT LASER OPERATION. IN ADDITION THIS CRYSTAL HAS LOW ASSOCIATED PHONON ENERGIES, SUBSTANTIALLY REDUCING THE PROBABILITY OF UPPER LASER LEVEL DEPLETION THROUGH NON-RADIATIVE TRANSITIONS. THE 5I8 5I5 PUMP TRANSITION AT 908 NM IS COMPATIBLE WITH STRAINED LAYER INGAAS QUANTUM WELL TECHNOLOGY. THIS IS A VIABLE PUMP LASER TECHNOLOGY SINCE STRAINED QUANTUM WELL DEVICES HAVE DEMONSTRATED HIGH RELIABILITY WITH STRAINED LAYERS NEAR THE CRITICAL THICKNESS. THE 908 NM OUTPUT REQUIRED ACCOMMODATES MUCH NARROWER STRAINED LAYER THICKNESSES RESULTING IN REDUCED STRESS ON THE ACTIVE LAYER AND IMPROVED RELIABLITY OF THE DIODE LASER PUMP SOURCE. ANTICIPATED BENEFITS/POTENTIAL COMMERCIAL APPLICATIONS - THE PROPOSED SYSTEM HOLDS PROMISE FOR EFFICIENT GENERATION OF NARROWBAND LASER RADIATION WHICH ISCOMPATIBLE WITH THE CS ATOMIC RESONANCE FILTER. IN ADDITION TO SUBMARINE COMMUNICATIONS, THE BLUE-GREEN OUTPUTS ARE SUITABLE FOR APPLICATIONS IN FLUORESCENCE SPECTROSCOPY, HIGH RESOLUTION IMAGING, MEASUREMENTSAND CONTROL SYSTEMS AS WELL AS OPTICAL MEMORY TECHNOLOGY. OTHER IMPORTANT APPLICATIONS WILL UTILIZE