Bright Coherent Optical Waveforms from the Infrared to the Vacuum Ultraviolet for Manipulation and Detection of Molecules

: In this grant we made four major advances in extreme nonlinear optics and strong field science. First we showed that it is possible to induce electromagnetic transparency in an atom (He) subject to intense vacuum VUV radiation. This allowed us to enhance or suppress multiphoton ionization of an atom by manipulating two interfering pathways for ionization. Second visualized in space and time the dynamic evolution of the entire ten-electron valence shell electron density as a molecular bond ruptures ? a feat that was never before achieved. Third, we theoretically developed a new and generalized realization of quasi phase matching (QPM) - called spatiotemporal quasi-phase matching - that generalizes traditional spatial QPM using layered media to space-time QPM. Instead of simply being described by a momentum mismatch, in general a nonlinear optical process may possess an energy mismatch, a momentum mismatch, or both an energy and momentum mismatch. Finally, we developed a new understanding of high harmonic generation that allowed us substantially increased the conversion efficiency into the vacuum ultraviolet region of the spectrum by using UV and VUV driving lasers.