RESONANCE IONIZATION MASS SPECTROMETRY SOLID STATE LASER

LASER RESONANCE IONIZATION MASS SPECTROMETRY (LRIMS) IS A POWERFUL ANALYTICAL TOOL THAT PERMITS THE DETECTION OF ULTRATRACE ELEMENTS AND ISOTOPES IN BIOLOGICAL SYSTEMS. THIS PERFORMANCE IS ACHIEVED BY COMBINING THE ELEMENTAL SELECTIVITY OF LASER RESONANCE IONIZATION WITH THE MASS SPECTROMETRY. IN ORDER TO MAKE LRIMS'S PRACTICAL, A TURN-KEY, ALL SOLID STATE TUNABLE ULTRAVIOLET LASER MUST BE DEVELOPED. ANALYSIS INCLUDE A MODEST, SEVERAL MILLIJOULE LASER OVER THE WAVELENGTH RANGE 250 NM TO 350NM, AND .3/CM BANDWIDTH WOULD BE AN IDEAL IONIZATION SOURCE. THE ELEMENTAL VAPOR REQUIRED PRIOR TO IONIZATION MAY BE EFFECTIVELY GENERATED BY A SECOND, MORE ENERGETIC, LONG PULSE ( > 1 MICRO SECOND) LASER. WE WILL DEVELOP A LASER SOURCE THAT ADDRESSES BOTH NEEDS. THE LASER IS BASED ON THE RECENTLY DEVELOPED FLASHLAMP PUMPED TITANIUM DOPED SAPPHIRE LASER. NONLINEAR OPTICS STEPS WILL GENERATE THE ULTRAVIOLET RADIATION. THE PHASE I PLAN IS FIRST TO IDENTIFY THE OPTIMUM CHOICE OF NONLINEAR OPTICAL MATERIALS AND TO DEMONSTRATE SECOND AND THIRD HARMONIC GENERATION. COVERAGE OF THE RANGE OF INTEREST, REQUIRED ENERGY, AND BANDWIDTH WILL BE DEMONSTRATED. PHASE I WILL DEMONSTRATE A TEMPORALLY PROGRAMMED PULSE OUTPUT FROM THE LASER CONSISTING OF A LONG PULSE, LOW PEAK POWER PART THAT WILL PRODUCE THE ELEMENTAL VAPOR AND SHORT PULSE, HIGH PEAK POWER PART FOR EFFICIENT FREQUENCY UP CONVERSION.